ALEXANDERS INC, 10-Q filed on November 03, 2025
v3.25.3
Cover
9 Months Ended
Sep. 30, 2025
shares
Cover [Abstract]  
Document Type 10-Q
Document Quarterly Report true
Document Period End Date Sep. 30, 2025
Document Transition Report false
Entity File Number 001-06064
Entity Registrant Name ALEXANDERS INC
Entity Incorporation, State or Country Code DE
Entity Tax Identification Number 51-0100517
Entity Address, Address Line One 210 Route 4 East,
Entity Address, City or Town Paramus,
Entity Address, State or Province NJ
Entity Address, Postal Zip Code 07652
City Area Code (201)
Local Phone Number 587-8541
Title of 12(b) Security Common Stock, $1 par value per share
Trading Symbol ALX
Security Exchange Name NYSE
Entity Current Reporting Status Yes
Entity Interactive Data Current Yes
Entity Filer Category Accelerated Filer
Entity Small Business false
Entity Emerging Growth Company false
Entity Shell Company false
Entity Common Stock, Shares Outstanding 5,107,290
Amendment Flag false
Document Fiscal Year Focus 2025
Document Fiscal Period Focus Q3
Entity Central Index Key 0000003499
Current Fiscal Year End Date --12-31
v3.25.3
Consolidated Balance Sheets (Unaudited) - USD ($)
$ in Thousands
Sep. 30, 2025
Dec. 31, 2024
Real Estate Investment Property, at Cost [Abstract]    
Land $ 32,271 $ 32,271
Buildings and leasehold improvements 1,065,198 1,046,132
Development and construction in progress 4,869 6,794
Total 1,102,338 1,085,197
Accumulated depreciation and amortization (466,619) (443,627)
Real estate, net 635,719 641,570
Cash and cash equivalents 286,142 338,532
Restricted cash 66,116 55,304
Tenant and other receivables 4,341 5,112
Receivable arising from the straight-lining of rents 109,645 111,750
Deferred leasing costs, net, including unamortized leasing fees to Vornado of $21,077 and $22,380, respectively 155,381 163,677
Other assets 38,896 25,350
Total assets 1,296,240 1,341,295
LIABILITIES AND EQUITY    
Mortgages payable, net of deferred debt issuance costs 987,100 988,019
Accounts payable and accrued expenses 44,992 38,743
Lease incentive liabilities 113,618 115,118
Total liabilities 1,167,914 1,164,436
Commitments and contingencies
Preferred stock: $1.00 par value per share; authorized, 3,000,000 shares; issued and outstanding, none 0 0
Common stock: $1.00 par value per share; authorized, 10,000,000 shares; issued, 5,173,450 shares; outstanding, 5,107,290 shares 5,173 5,173
Additional capital 35,159 34,765
Retained earnings 88,488 133,402
Accumulated other comprehensive (loss) income (126) 3,887
Equity before treasury stock 128,694 177,227
Treasury stock: 66,160 shares, at cost (368) (368)
Total equity 128,326 176,859
Total liabilities and equity 1,296,240 1,341,295
Related Party    
LIABILITIES AND EQUITY    
Other liabilities 499 1,159
Nonrelated Party    
LIABILITIES AND EQUITY    
Other liabilities $ 21,705 $ 21,397
v3.25.3
Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($)
$ in Thousands
Sep. 30, 2025
Dec. 31, 2024
Statement of Financial Position [Abstract]    
Unamortized leasing fees to Vornado $ 21,077 $ 22,380
Preferred stock: par value per share (in usd per share) $ 1.00 $ 1.00
Preferred stock: authorized shares (in shares) 3,000,000 3,000,000
Preferred stock: outstanding shares (in shares) 0 0
Preferred stock: issued shares (in shares) 0 0
Common stock: par value per share (in usd per share) $ 1.00 $ 1.00
Common stock: authorized shares (in shares) 10,000,000 10,000,000
Common stock: issued shares (in shares) 5,173,450 5,173,450
Common stock: outstanding shares (in shares) 5,107,290 5,107,290
Treasury stock: shares (in shares) 66,160 66,160
v3.25.3
Consolidated Statements of Income (Unaudited) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
REVENUES        
Rental revenues $ 53,424 $ 55,675 $ 159,928 $ 170,464
EXPENSES        
Operating, including fees to Vornado of $1,253, $1,828, $4,435 and $4,932, respectively (26,693) (26,446) (78,191) (76,700)
Depreciation and amortization (9,018) (7,972) (26,324) (26,146)
General and administrative, including management fees to Vornado of $610, $610, $1,830 and $1,830, respectively (1,349) (1,423) (4,895) (5,058)
Total expenses (37,060) (35,841) (109,410) (107,904)
Interest and other income 3,682 6,105 11,555 20,321
Interest and debt expense (14,078) (19,261) (37,673) (51,714)
Net income $ 5,968 $ 6,678 $ 24,400 $ 31,167
Net income per common share - basic (in usd per share) $ 1.16 $ 1.30 $ 4.75 $ 6.07
Net income per common share - diluted (in usd per share) $ 1.16 $ 1.30 $ 4.75 $ 6.07
Weighted average shares outstanding - basic (in shares) 5,135,956 5,133,534 5,134,705 5,132,043
Weighted average shares outstanding - diluted (in shares) 5,135,956 5,133,534 5,134,705 5,132,043
v3.25.3
Consolidated Statements of Income (Unaudited) (Parenthetical) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Operating fees to Vornado $ 26,693 $ 26,446 $ 78,191 $ 76,700
General and administrative 1,349 1,423 4,895 5,058
Related Party        
Operating fees to Vornado 1,253 1,828 4,435 4,932
General and administrative $ 610 $ 610 $ 1,830 $ 1,830
v3.25.3
Consolidated Statements of Comprehensive Income (Unaudited) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Statement of Comprehensive Income [Abstract]        
Net income $ 5,968 $ 6,678 $ 24,400 $ 31,167
Other comprehensive income (loss):        
Change in fair value of interest rate derivatives 23 (5,408) (4,013) (9,308)
Comprehensive income $ 5,991 $ 1,270 $ 20,387 $ 21,859
v3.25.3
Consolidated Statements of Changes in Equity (Unaudited) - USD ($)
$ in Thousands
Total
Common Stock
Additional Capital
Retained Earnings
Accumulated  Other Comprehensive (Loss) Income
Treasury Stock
Beginning balance, (in shares) at Dec. 31, 2023   5,173,000        
Beginning balance, value at Dec. 31, 2023 $ 237,657 $ 5,173 $ 34,315 $ 182,336 $ 16,201 $ (368)
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Net income 31,167     31,167    
Dividends paid (69,277)     (69,277)    
Change in fair value of interest rate derivatives (9,308)       (9,308)  
Deferred stock unit grants 450   450      
Ending balance, (in shares) at Sep. 30, 2024   5,173,000        
Ending balance, value at Sep. 30, 2024 190,689 $ 5,173 34,765 144,226 6,893 (368)
Beginning balance, (in shares) at Jun. 30, 2024   5,173,000        
Beginning balance, value at Jun. 30, 2024 212,520 $ 5,173 34,765 160,649 12,301 (368)
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Net income 6,678     6,678    
Dividends paid (23,101)     (23,101)    
Change in fair value of interest rate derivatives (5,408)       (5,408)  
Ending balance, (in shares) at Sep. 30, 2024   5,173,000        
Ending balance, value at Sep. 30, 2024 $ 190,689 $ 5,173 34,765 144,226 6,893 (368)
Beginning balance, (in shares) at Dec. 31, 2024 5,173,450 5,173,000        
Beginning balance, value at Dec. 31, 2024 $ 176,859 $ 5,173 34,765 133,402 3,887 (368)
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Net income 24,400     24,400    
Dividends paid (69,314)     (69,314)    
Change in fair value of interest rate derivatives (4,013)       (4,013)  
Deferred stock unit grants $ 394   394      
Ending balance, (in shares) at Sep. 30, 2025 5,173,450 5,173,000        
Ending balance, value at Sep. 30, 2025 $ 128,326 $ 5,173 35,159 88,488 (126) (368)
Beginning balance, (in shares) at Jun. 30, 2025   5,173,000        
Beginning balance, value at Jun. 30, 2025 145,447 $ 5,173 35,159 105,632 (149) (368)
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Net income 5,968     5,968    
Dividends paid (23,112)     (23,112)    
Change in fair value of interest rate derivatives $ 23       23  
Ending balance, (in shares) at Sep. 30, 2025 5,173,450 5,173,000        
Ending balance, value at Sep. 30, 2025 $ 128,326 $ 5,173 $ 35,159 $ 88,488 $ (126) $ (368)
v3.25.3
Consolidated Statements of Changes in Equity (Unaudited) (Parenthetical) - $ / shares
3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Statement of Stockholders' Equity [Abstract]        
Dividends per common share (in usd per share) $ 4.50 $ 4.50 $ 13.50 $ 13.50
v3.25.3
Consolidated Statements of Cash Flows (Unaudited) - USD ($)
$ in Thousands
9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
CASH FLOWS FROM OPERATING ACTIVITIES    
Net income $ 24,400 $ 31,167
Adjustments to reconcile net income to net cash provided by operating activities:    
Depreciation and amortization, including amortization of debt issuance costs 28,709 28,470
Straight-lining of rents 2,105 11,880
Interest rate cap premium amortization 470 6,213
Stock-based compensation expense 394 450
Other non-cash adjustments 6,529 (1,664)
Change in operating assets and liabilities:    
Tenant and other receivables 771 529
Other assets (19,271) (161,750)
Amounts due to Vornado (497) 36
Accounts payable and accrued expenses 7,925 (5,639)
Lease incentive liabilities (1,500) 113,618
Other liabilities (15) (14)
Net cash provided by operating activities 50,020 23,296
CASH FLOWS FROM INVESTING ACTIVITIES    
Construction in progress and real estate additions (18,986) (9,836)
Proceeds from interest rate cap 0 6,563
Net cash used in investing activities (18,986) (3,273)
CASH FLOWS FROM FINANCING ACTIVITIES    
Dividends paid (69,314) (69,277)
Debt repayments (3,189) (500,000)
Proceeds from borrowing 0 400,000
Debt issuance costs (109) (6,547)
Net cash used in financing activities (72,612) (175,824)
Net decrease in cash and cash equivalents and restricted cash (41,578) (155,801)
Cash and cash equivalents and restricted cash at beginning of period 393,836 552,977
Cash and cash equivalents and restricted cash at end of period 352,258 397,176
RECONCILIATION OF CASH AND CASH EQUIVALENTS AND RESTRICTED CASH    
Cash and cash equivalents at beginning of period 338,532 531,855
Restricted cash at beginning of period 55,304 21,122
Cash and cash equivalents and restricted cash at beginning of period 393,836 552,977
Cash and cash equivalents at end of period 286,142 354,817
Restricted cash at end of period 66,116 42,359
Cash and cash equivalents and restricted cash at end of period 352,258 397,176
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION    
Cash payments for interest 34,052 51,426
NON-CASH TRANSACTIONS    
Liability for real estate additions, including $182 and $192, respectively for development fees due to Vornado 1,157 6,143
Write-off of fully depreciated assets $ 0 $ 1,760
v3.25.3
Consolidated Statements of Cash Flows (Unaudited) (Parenthetical) - USD ($)
$ in Thousands
9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Development fees $ 1,157 $ 6,143
Vornado    
Development fees $ 182 $ 192
v3.25.3
Organization
9 Months Ended
Sep. 30, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Organization Organization
Alexander’s, Inc. (NYSE: ALX) is a real estate investment trust (“REIT”), incorporated in Delaware, engaged in leasing, managing, developing and redeveloping its properties. All references to “we,” “us,” “our,” “Company” and “Alexander’s” refer to Alexander’s, Inc. and its consolidated subsidiaries. We are managed by, and our properties are leased and developed by, Vornado Realty Trust (“Vornado”) (NYSE: VNO). We have five properties in New York City.
v3.25.3
Basis of Presentation
9 Months Ended
Sep. 30, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Basis of Presentation Basis of Presentation
The accompanying consolidated financial statements are unaudited and include the accounts of Alexander’s and its consolidated subsidiaries. All adjustments (which include only normal recurring adjustments) necessary to present fairly the financial position, results of operations and changes in cash flows have been made. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) have been condensed or omitted. These consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q of the Securities and Exchange Commission (“SEC”) and should be read in conjunction with the consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2024, as filed with the SEC.
We have made estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates. The results of operations for the three and nine months ended September 30, 2025 are not necessarily indicative of the operating results for the full year.
v3.25.3
Recently Issued Accounting Literature
9 Months Ended
Sep. 30, 2025
Accounting Standards Update and Change in Accounting Principle [Abstract]  
Recently Issued Accounting Literature Recently Issued Accounting Literature
In December 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”). ASU 2023-09 requires entities to disclose additional information with respect to the effective tax rate reconciliation and to disclose the disaggregation by jurisdiction of income tax expense and income taxes paid. ASU 2023-09 is effective for fiscal years beginning after December 15, 2024, with early adoption permitted. We have evaluated the impact of this standard and do not expect it to have a material impact on our consolidated financial statements.
In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”), and in January 2025, the FASB issued ASU 2025-01, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Clarifying the Effective Date (“ASU 2025-01”). ASU 2024-03 requires additional disclosure of the nature of expenses included in the income statement as well as disclosures about specific types of expenses included in the expense captions presented in the income statement. ASU 2024-03, as clarified by ASU 2025-01, is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027, with early adoption permitted. We are currently evaluating the impact of these standards on our consolidated financial statements.
v3.25.3
Revenue Recognition
9 Months Ended
Sep. 30, 2025
Revenue from Contract with Customer [Abstract]  
Revenue Recognition Revenue Recognition
The following is a summary of revenue sources for the three and nine months ended September 30, 2025 and 2024.
For the Three Months Ended September 30,For the Nine Months Ended September 30,
(Amounts in thousands)2025202420252024
Lease revenues$50,944 $53,244 $153,172 $163,878 
Parking revenue1,214 1,168 3,628 3,483 
Tenant services1,266 1,263 3,128 3,103 
Rental revenues$53,424 $55,675 $159,928 $170,464 
The components of lease revenues for the three and nine months ended September 30, 2025 and 2024 are as follows:
For the Three Months Ended September 30,For the Nine Months Ended September 30,
(Amounts in thousands)2025202420252024
Fixed lease revenues$33,922 $35,608 $102,285 $112,542 
Variable lease revenues17,022 17,636 50,887 51,336 
Lease revenues$50,944 $53,244 $153,172 $163,878 

Bloomberg L.P. (“Bloomberg”) accounted for revenue of $96,655,000 and $93,179,000 for the nine months ended September 30, 2025 and 2024, respectively, representing approximately 60% and 55% of our rental revenues in each period, respectively. No other tenant accounted for more than 10% of our rental revenues. If we were to lose Bloomberg as a tenant, or if Bloomberg were to be unable to fulfill its obligations under its lease, it would adversely affect our results of operations and financial condition. In order to assist us in our continuing assessment of Bloomberg’s creditworthiness, we receive certain confidential financial information and metrics from Bloomberg. In addition, we access and evaluate financial information regarding Bloomberg from other private sources, as well as publicly available data.
On January 31, 2025, Home Depot’s 83,000 square foot lease at the retail portion of our 731 Lexington Avenue property expired. Annual rental revenues from Home Depot were approximately $15,000,000.
In May 2024, Alexander’s and Bloomberg reached an agreement to extend the leases covering approximately 947,000 square feet at our 731 Lexington Avenue property that were scheduled to expire in February 2029 for a term of eleven years to February 2040. Upon execution of this lease extension, we paid a $32,000,000 leasing commission, of which $26,500,000 was to a third-party broker and $5,500,000 was to Vornado.
On December 3, 2022, IKEA closed its 112,000 square foot store at our Rego Park I property under a lease that was set to expire in December 2030. The lease included a right to terminate effective no earlier than March 16, 2026, subject to payment of rent through the termination date and an additional termination payment equal to the lesser of $10,000,000 or the amount of rent due under the remaining term. On September 27, 2023, we entered into a lease modification agreement with IKEA which accelerated its lease termination date to April 1, 2024. During the fourth quarter of 2023 and the first quarter of 2024, IKEA paid its remaining rent obligation through March 16, 2026 and the $10,000,000 termination payment.
v3.25.3
Related Party Transactions
9 Months Ended
Sep. 30, 2025
Related Party Transactions [Abstract]  
Related Party Transactions Related Party Transactions
Vornado
As of September 30, 2025, Vornado owned 32.4% of our outstanding common stock. We are managed by, and our properties are leased and developed by, Vornado, pursuant to the agreements described below, which expire in March of each year and are automatically renewable.
Management and Development Agreements
We pay Vornado an annual management fee equal to the sum of (i) $2,800,000, (ii) 2% of gross revenue from the Rego Park II shopping center, (iii) $0.50 per square foot of the tenant-occupied office and retail space at 731 Lexington Avenue, and (iv) $387,000, escalating at 3% per annum, for managing the common area of 731 Lexington Avenue. Vornado is also entitled to a development fee equal to 6% of development costs, as defined.
Leasing and Other Agreements
Vornado also provides us with leasing services for a fee of 3% of rent for the first ten years of a lease term, 2% of rent for the eleventh through the twentieth year of a lease term, and 1% of rent for the twenty-first through thirtieth year of a lease term, subject to the payment of rents by tenants. Under the agreements in effect prior to May 1, 2024, in the event third-party real estate brokers were used, the fees to Vornado increased by 1% and Vornado was responsible for the fees to the third-party real estate brokers (“Third-Party Lease Commissions”). On May 1, 2024, our Board of Directors approved amendments to the leasing agreements, subject to applicable lender consents, pursuant to which the Company is responsible for any Third-Party Lease Commissions and, in such circumstances, Vornado’s fee is one-third of the applicable Third-Party Lease Commission.
Vornado is also entitled to a commission upon the sale of any of our assets equal to 3% of gross proceeds, as defined, for asset sales less than $50,000,000 and 1% of gross proceeds, as defined, for asset sales of $50,000,000 or more.
We also have agreements with Building Maintenance Services LLC, a wholly owned subsidiary of Vornado, to supervise (i) cleaning, engineering and security services at our 731 Lexington Avenue property and (ii) security services at our Rego Park I and Rego Park II properties and The Alexander apartment tower. In addition, we have an agreement with a wholly owned subsidiary of Vornado to manage the parking garages at our Rego Park I and Rego Park II properties.
The following is a summary of fees earned by Vornado under the various agreements discussed above.
 For the Three Months Ended September 30,For the Nine Months Ended September 30,
(Amounts in thousands)2025202420252024
Company management fees$700 $700 $2,100 $2,100 
Development fees182 192 808 318 
Leasing fees303 — 545 5,555 
Property management, cleaning, engineering, parking and security fees1,117 1,688 4,040 4,537 
$2,302 $2,580 $7,493 $12,510 
As of September 30, 2025, the amounts due to Vornado were $182,000 for development fees, $182,000 for leasing fees and $135,000 for management, property management, cleaning, engineering and security fees. As of December 31, 2024, the amounts due to Vornado were $642,000 for management, property management, cleaning, engineering and security fees, $346,000 for development fees and $171,000 for leasing fees.
v3.25.3
Mortgages Payable
9 Months Ended
Sep. 30, 2025
Debt Disclosure [Abstract]  
Mortgages Payable Mortgages Payable
The following is a summary of our outstanding mortgages payable as of September 30, 2025 and December 31, 2024. We may refinance our maturing debt as it comes due or choose to pay it down.
  
Interest Rate as of September 30, 2025
Balance as of
(Amounts in thousands)MaturitySeptember 30, 2025December 31, 2024
First mortgages secured by:
731 Lexington Avenue, office condominiumOct. 09, 20285.04%$400,000 $400,000 
731 Lexington Avenue, retail condominium (1)(2)
Oct. 03, 20255.76%300,000 300,000 
Rego Park II shopping center (1)(3)
Dec. 12, 20255.60%199,355 202,544 
The Alexander apartment towerNov. 01, 20272.63%94,000 94,000 
Total993,355 996,544 
Deferred debt issuance costs, net of accumulated amortization of $9,766 and $7,381, respectively
(6,255)(8,525)
$987,100 $988,019 
(1)Interest rate listed represents the rate in effect as of September 30, 2025 based on SOFR as of contractual reset date plus contractual spread, adjusted for hedging instruments as applicable.
(2)Interest at SOFR plus 1.51%.
(3)Interest at SOFR plus 1.45% (SOFR is capped at a rate of 4.15% through December 2025).
The $300,000,000 non-recourse mortgage loan on the retail condominium of our 731 Lexington Avenue property was scheduled to mature on August 5, 2025. On August 1, 2025, we entered into a 60-day extension with the lenders. The Company did not repay the loan on the extended maturity date of October 3, 2025. The Company is in discussions with the lenders regarding a potential loan restructuring.
v3.25.3
Stock-Based Compensation
9 Months Ended
Sep. 30, 2025
Share-Based Payment Arrangement [Abstract]  
Stock-Based Compensation Stock-Based Compensation
We account for stock-based compensation in accordance with Accounting Standards Codification (“ASC”) Topic 718, Compensation – Stock Compensation (“ASC 718”). Our 2016 Omnibus Stock Plan (the “Plan”) provides for grants of incentive and non-qualified stock options, restricted stock, stock appreciation rights, deferred stock units (“DSUs”) and performance shares, as defined, to the directors, officers and employees of the Company and Vornado.
In May 2025, we granted each of the members of our Board of Directors 346 DSUs with a market value of $75,000 per grant. The grant date fair value of these awards was $56,250 per grant, or $394,000 in the aggregate, in accordance with ASC 718. The DSUs entitle the holders to receive shares of the Company’s common stock without the payment of any consideration. The DSUs vested immediately and accordingly, were expensed on the date of grant, but the shares of common stock underlying the DSUs are not deliverable to the grantee until the grantee is no longer serving on the Company’s Board of Directors or until a later date selected by the grantee. As of September 30, 2025, there were 28,666 DSUs outstanding and 477,121 shares were available for future grant under the Plan.
v3.25.3
Fair Value Measurements
9 Months Ended
Sep. 30, 2025
Fair Value Disclosures [Abstract]  
Fair Value Measurements Fair Value Measurements
ASC Topic 820, Fair Value Measurement (“ASC 820”) defines fair value and establishes a framework for measuring fair value. ASC 820 establishes a fair value hierarchy that prioritizes observable and unobservable inputs used to measure fair value into three levels: Level 1 – quoted prices (unadjusted) in active markets that are accessible at the measurement date for assets or liabilities that are highly liquid and are actively traded in secondary markets; Level 2 – observable prices that are based on inputs not quoted in active markets, but corroborated by market data; and Level 3 – unobservable inputs that are used when little or no market data is available. The fair value hierarchy gives the highest priority to Level 1 inputs and the lowest priority to Level 3 inputs. In determining fair value, we utilize valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible as well as consider counterparty credit risk in our assessment of fair value.
8.Fair Value Measurements - continued
Financial Assets and Liabilities Measured at Fair Value
Financial assets measured at fair value on our consolidated balance sheet as of September 30, 2025 consist of an interest rate cap, which is presented in the table below based on its level in the fair value hierarchy. There were no financial liabilities measured at fair value as of September 30, 2025.
 As of September 30, 2025
(Amounts in thousands)TotalLevel 1Level 2Level 3
Interest rate derivative (included in other assets)$$— $$— 

Financial assets measured at fair value on our consolidated balance sheet as of December 31, 2024 consist of interest rate derivatives, which are presented in the table below based on their level in the fair value hierarchy. There were no financial liabilities measured at fair value as of December 31, 2024. 
 As of December 31, 2024
(Amounts in thousands)TotalLevel 1Level 2Level 3
Interest rate derivatives (included in other assets)$4,487 $— $4,487 $— 
Interest Rate Derivatives
We recognize the fair value of all interest rate derivatives in “other assets” or “other liabilities” on our consolidated balance sheets and since all of our interest rate derivatives have been designated as cash flow hedges, changes in the fair value are recognized in other comprehensive income. The table below summarizes our interest rate derivatives, all of which hedge the interest rate risk attributable to the variable rate debt noted as of September 30, 2025 and December 31, 2024, respectively.
Fair Value as ofAs of September 30, 2025
(Amounts in thousands)September 30, 2025December 31, 2024Notional AmountSwapped RateExpiration Date
Interest rate swap related to:
731 Lexington Avenue mortgage loan, retail condominium$— $4,117 N/AN/AN/A
Interest rate cap related to:
Rego Park II shopping center mortgage loan370 $199,355 (1)12/25
Included in other assets$$4,487 
(1)SOFR cap strike rate of 4.15%.
Financial Assets and Liabilities not Measured at Fair Value
Financial assets and liabilities that are not measured at fair value on our consolidated balance sheets include cash equivalents and mortgages payable. Cash equivalents are carried at cost, which approximates fair value due to their short-term maturities and are classified as Level 1. The fair value of our mortgages payable is calculated by discounting the future contractual cash flows of these instruments using current risk-adjusted rates available to borrowers with similar credit ratings, which are provided by a third-party specialist, and is classified as Level 2. The table below summarizes the carrying amount and fair value of these financial instruments as of September 30, 2025 and December 31, 2024, respectively.
 As of September 30, 2025As of December 31, 2024
(Amounts in thousands)Carrying
Amount
Fair
Value
Carrying
Amount
Fair
Value
Assets:
Cash equivalents
$67,135 $67,135 $61,889 $61,889 
Liabilities:
Mortgages payable (excluding deferred debt issuance costs, net)$993,355 $983,675 $996,544 $967,941 
v3.25.3
Commitments and Contingencies
9 Months Ended
Sep. 30, 2025
Commitments and Contingencies Disclosure [Abstract]  
Commitments and Contingencies Commitments and Contingencies
Insurance
We maintain general liability insurance with limits of $300,000,000 per occurrence and per property, which includes communicable disease coverage, and all-risk property and rental value insurance coverage with limits of $1.7 billion per occurrence, including coverage for acts of terrorism, with sub-limits for certain perils such as floods and earthquakes on each of our properties and excluding communicable disease coverage.
Fifty Ninth Street Insurance Company, LLC (“FNSIC”), our wholly owned consolidated subsidiary, acts as a direct insurer for coverage for acts of terrorism, including nuclear, biological, chemical and radiological (“NBCR”) acts, as defined by the Terrorism Risk Insurance Act of 2002, as amended to date and which has been extended through December 2027. Coverage for acts of terrorism (including NBCR acts) is up to $1.7 billion per occurrence and in the aggregate. Coverage for acts of terrorism (excluding NBCR acts) is fully reinsured by third party insurance companies and the Federal government with no exposure to FNSIC. For NBCR acts, FNSIC is responsible for a $348,000 deductible and 20% of the balance of a covered loss, and the Federal government is responsible for the remaining 80% of a covered loss. We are ultimately responsible for any loss incurred by FNSIC.
We continue to monitor the state of the insurance market and the scope and costs of coverage for acts of terrorism or other events. However, we cannot anticipate what coverage will be available on commercially reasonable terms in the future. We are responsible for uninsured losses and for deductibles and losses in excess of our insurance coverage, which could be material.
Our loans contain customary covenants requiring us to maintain insurance. Although we believe that we have adequate insurance coverage for purposes of these agreements, we may not be able to obtain an equivalent amount of coverage at reasonable costs in the future. If lenders insist on greater coverage than we are able to obtain, it could adversely affect our ability to finance or refinance our properties.
Other
There are various legal actions brought against us from time-to-time in the ordinary course of business. In our opinion, the outcome of such pending matters in the aggregate will not have a material effect on our financial position, results of operations or cash flows.
v3.25.3
Earnings Per Share
9 Months Ended
Sep. 30, 2025
Earnings Per Share [Abstract]  
Earnings Per Share Earnings Per Share
The following table sets forth the computation of basic and diluted income per share, including the number of shares used in computing basic and diluted income per share. Basic income per share is determined using the weighted average shares of common stock (including deferred stock units) outstanding during the period. Diluted income per share is determined using the weighted average shares of common stock (including deferred stock units) outstanding during the period, and assumes all potentially dilutive securities were converted into common shares at the earliest date possible. There were no potentially dilutive securities outstanding during the three and nine months ended September 30, 2025 and 2024.
 For the Three Months Ended September 30,For the Nine Months
Ended September 30,
(Amounts in thousands, except share and per share amounts)
2025202420252024
Net income $5,968 $6,678 $24,400 $31,167 
Weighted average shares outstanding – basic and diluted
5,135,956 5,133,534 5,134,705 5,132,043 
Net income per common share – basic and diluted$1.16 $1.30 $4.75 $6.07 
v3.25.3
Segment Information
9 Months Ended
Sep. 30, 2025
Segment Reporting [Abstract]  
Segment Information Segment Information
We have determined that our properties, which are considered our operating segments, have similar economic characteristics and meet the criteria that permit these operating segments to be aggregated into one reportable segment (the leasing, management, development and redevelopment of properties in New York City). Net operating income (“NOI”) represents total revenues less operating expenses. The Company’s chief operating decision maker ("CODM") is its Chief Executive Officer, who considers NOI to be the financial measure of segment profit and loss for making decisions on how to allocate resources and assessing the performance of the reportable segment. Asset information by segment is not reported as the CODM does not use this measure to assess segment performance or to make resource allocation decisions.
Below is a summary of financial information for the three and nine months ended September 30, 2025 and 2024.
 For the Three Months
Ended September 30,
For the Nine Months
Ended September 30,
(Amounts in thousands)2025202420252024
Rental revenues$53,424 $55,675 $159,928 $170,464 
Real estate tax expense(15,755)(15,018)(45,439)(43,931)
Other segment expenses (1)
(10,938)(11,428)(32,752)(32,769)
Total operating expenses(26,693)(26,446)(78,191)(76,700)
NOI$26,731 $29,229 $81,737 $93,764 
(1)Includes various expenses associated with operating our properties including but not limited to ground rent, insurance, repairs and maintenance and utilities.
Below is a reconciliation of NOI to net income for the three and nine months ended September 30, 2025 and 2024.
 For the Three Months Ended September 30,For the Nine Months
Ended September 30,
(Amounts in thousands)2025202420252024
NOI$26,731 $29,229 $81,737 $93,764 
Interest and debt expense(14,078)(19,261)(37,673)(51,714)
Interest and other income3,682 6,105 11,555 20,321 
General and administrative(1,349)(1,423)(4,895)(5,058)
Depreciation and amortization(9,018)(7,972)(26,324)(26,146)
Net income$5,968 $6,678 $24,400 $31,167 
v3.25.3
Insider Trading Arrangements
3 Months Ended
Sep. 30, 2025
Trading Arrangements, by Individual  
Rule 10b5-1 Arrangement Adopted false
Non-Rule 10b5-1 Arrangement Adopted false
Rule 10b5-1 Arrangement Terminated false
Non-Rule 10b5-1 Arrangement Terminated false
v3.25.3
Basis of Presentation (Policies)
9 Months Ended
Sep. 30, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Basis of Presentation
The accompanying consolidated financial statements are unaudited and include the accounts of Alexander’s and its consolidated subsidiaries. All adjustments (which include only normal recurring adjustments) necessary to present fairly the financial position, results of operations and changes in cash flows have been made. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) have been condensed or omitted. These consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q of the Securities and Exchange Commission (“SEC”) and should be read in conjunction with the consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2024, as filed with the SEC.
We have made estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates. The results of operations for the three and nine months ended September 30, 2025 are not necessarily indicative of the operating results for the full year.
Recently Issued Accounting Literature
In December 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”). ASU 2023-09 requires entities to disclose additional information with respect to the effective tax rate reconciliation and to disclose the disaggregation by jurisdiction of income tax expense and income taxes paid. ASU 2023-09 is effective for fiscal years beginning after December 15, 2024, with early adoption permitted. We have evaluated the impact of this standard and do not expect it to have a material impact on our consolidated financial statements.
In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”), and in January 2025, the FASB issued ASU 2025-01, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Clarifying the Effective Date (“ASU 2025-01”). ASU 2024-03 requires additional disclosure of the nature of expenses included in the income statement as well as disclosures about specific types of expenses included in the expense captions presented in the income statement. ASU 2024-03, as clarified by ASU 2025-01, is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027, with early adoption permitted. We are currently evaluating the impact of these standards on our consolidated financial statements.
Stock-Based Compensation
We account for stock-based compensation in accordance with Accounting Standards Codification (“ASC”) Topic 718, Compensation – Stock Compensation (“ASC 718”). Our 2016 Omnibus Stock Plan (the “Plan”) provides for grants of incentive and non-qualified stock options, restricted stock, stock appreciation rights, deferred stock units (“DSUs”) and performance shares, as defined, to the directors, officers and employees of the Company and Vornado.
Fair Value Measurements
ASC Topic 820, Fair Value Measurement (“ASC 820”) defines fair value and establishes a framework for measuring fair value. ASC 820 establishes a fair value hierarchy that prioritizes observable and unobservable inputs used to measure fair value into three levels: Level 1 – quoted prices (unadjusted) in active markets that are accessible at the measurement date for assets or liabilities that are highly liquid and are actively traded in secondary markets; Level 2 – observable prices that are based on inputs not quoted in active markets, but corroborated by market data; and Level 3 – unobservable inputs that are used when little or no market data is available. The fair value hierarchy gives the highest priority to Level 1 inputs and the lowest priority to Level 3 inputs. In determining fair value, we utilize valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible as well as consider counterparty credit risk in our assessment of fair value.
v3.25.3
Revenue Recognition (Tables)
9 Months Ended
Sep. 30, 2025
Revenue from Contract with Customer [Abstract]  
Schedule of Revenue
The following is a summary of revenue sources for the three and nine months ended September 30, 2025 and 2024.
For the Three Months Ended September 30,For the Nine Months Ended September 30,
(Amounts in thousands)2025202420252024
Lease revenues$50,944 $53,244 $153,172 $163,878 
Parking revenue1,214 1,168 3,628 3,483 
Tenant services1,266 1,263 3,128 3,103 
Rental revenues$53,424 $55,675 $159,928 $170,464 
Schedule of Components of Lease Revenue
The components of lease revenues for the three and nine months ended September 30, 2025 and 2024 are as follows:
For the Three Months Ended September 30,For the Nine Months Ended September 30,
(Amounts in thousands)2025202420252024
Fixed lease revenues$33,922 $35,608 $102,285 $112,542 
Variable lease revenues17,022 17,636 50,887 51,336 
Lease revenues$50,944 $53,244 $153,172 $163,878 
v3.25.3
Related Party Transactions (Tables)
9 Months Ended
Sep. 30, 2025
Related Party Transactions [Abstract]  
Schedule of Fees to Vornado
The following is a summary of fees earned by Vornado under the various agreements discussed above.
 For the Three Months Ended September 30,For the Nine Months Ended September 30,
(Amounts in thousands)2025202420252024
Company management fees$700 $700 $2,100 $2,100 
Development fees182 192 808 318 
Leasing fees303 — 545 5,555 
Property management, cleaning, engineering, parking and security fees1,117 1,688 4,040 4,537 
$2,302 $2,580 $7,493 $12,510 
v3.25.3
Mortgages Payable (Tables)
9 Months Ended
Sep. 30, 2025
Debt Disclosure [Abstract]  
Schedule of Long-term Debt Instruments
The following is a summary of our outstanding mortgages payable as of September 30, 2025 and December 31, 2024. We may refinance our maturing debt as it comes due or choose to pay it down.
  
Interest Rate as of September 30, 2025
Balance as of
(Amounts in thousands)MaturitySeptember 30, 2025December 31, 2024
First mortgages secured by:
731 Lexington Avenue, office condominiumOct. 09, 20285.04%$400,000 $400,000 
731 Lexington Avenue, retail condominium (1)(2)
Oct. 03, 20255.76%300,000 300,000 
Rego Park II shopping center (1)(3)
Dec. 12, 20255.60%199,355 202,544 
The Alexander apartment towerNov. 01, 20272.63%94,000 94,000 
Total993,355 996,544 
Deferred debt issuance costs, net of accumulated amortization of $9,766 and $7,381, respectively
(6,255)(8,525)
$987,100 $988,019 
(1)Interest rate listed represents the rate in effect as of September 30, 2025 based on SOFR as of contractual reset date plus contractual spread, adjusted for hedging instruments as applicable.
(2)Interest at SOFR plus 1.51%.
(3)Interest at SOFR plus 1.45% (SOFR is capped at a rate of 4.15% through December 2025).
v3.25.3
Fair Value Measurements (Tables)
9 Months Ended
Sep. 30, 2025
Fair Value Disclosures [Abstract]  
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis
Financial assets measured at fair value on our consolidated balance sheet as of September 30, 2025 consist of an interest rate cap, which is presented in the table below based on its level in the fair value hierarchy. There were no financial liabilities measured at fair value as of September 30, 2025.
 As of September 30, 2025
(Amounts in thousands)TotalLevel 1Level 2Level 3
Interest rate derivative (included in other assets)$$— $$— 

Financial assets measured at fair value on our consolidated balance sheet as of December 31, 2024 consist of interest rate derivatives, which are presented in the table below based on their level in the fair value hierarchy. There were no financial liabilities measured at fair value as of December 31, 2024. 
 As of December 31, 2024
(Amounts in thousands)TotalLevel 1Level 2Level 3
Interest rate derivatives (included in other assets)$4,487 $— $4,487 $— 
Schedule of Interest Rate Derivatives The table below summarizes our interest rate derivatives, all of which hedge the interest rate risk attributable to the variable rate debt noted as of September 30, 2025 and December 31, 2024, respectively.
Fair Value as ofAs of September 30, 2025
(Amounts in thousands)September 30, 2025December 31, 2024Notional AmountSwapped RateExpiration Date
Interest rate swap related to:
731 Lexington Avenue mortgage loan, retail condominium$— $4,117 N/AN/AN/A
Interest rate cap related to:
Rego Park II shopping center mortgage loan370 $199,355 (1)12/25
Included in other assets$$4,487 
(1)SOFR cap strike rate of 4.15%.
Schedule of Carrying Amount and Fair Value of Financial Instruments The table below summarizes the carrying amount and fair value of these financial instruments as of September 30, 2025 and December 31, 2024, respectively.
 As of September 30, 2025As of December 31, 2024
(Amounts in thousands)Carrying
Amount
Fair
Value
Carrying
Amount
Fair
Value
Assets:
Cash equivalents
$67,135 $67,135 $61,889 $61,889 
Liabilities:
Mortgages payable (excluding deferred debt issuance costs, net)$993,355 $983,675 $996,544 $967,941 
v3.25.3
Earnings Per Share (Tables)
9 Months Ended
Sep. 30, 2025
Earnings Per Share [Abstract]  
Schedule of Earnings Per Share, Basic and Diluted
The following table sets forth the computation of basic and diluted income per share, including the number of shares used in computing basic and diluted income per share. Basic income per share is determined using the weighted average shares of common stock (including deferred stock units) outstanding during the period. Diluted income per share is determined using the weighted average shares of common stock (including deferred stock units) outstanding during the period, and assumes all potentially dilutive securities were converted into common shares at the earliest date possible. There were no potentially dilutive securities outstanding during the three and nine months ended September 30, 2025 and 2024.
 For the Three Months Ended September 30,For the Nine Months
Ended September 30,
(Amounts in thousands, except share and per share amounts)
2025202420252024
Net income $5,968 $6,678 $24,400 $31,167 
Weighted average shares outstanding – basic and diluted
5,135,956 5,133,534 5,134,705 5,132,043 
Net income per common share – basic and diluted$1.16 $1.30 $4.75 $6.07 
v3.25.3
Segment Information (Tables)
9 Months Ended
Sep. 30, 2025
Segment Reporting [Abstract]  
Schedule of Segment Reporting Information, by Segment
Below is a summary of financial information for the three and nine months ended September 30, 2025 and 2024.
 For the Three Months
Ended September 30,
For the Nine Months
Ended September 30,
(Amounts in thousands)2025202420252024
Rental revenues$53,424 $55,675 $159,928 $170,464 
Real estate tax expense(15,755)(15,018)(45,439)(43,931)
Other segment expenses (1)
(10,938)(11,428)(32,752)(32,769)
Total operating expenses(26,693)(26,446)(78,191)(76,700)
NOI$26,731 $29,229 $81,737 $93,764 
(1)Includes various expenses associated with operating our properties including but not limited to ground rent, insurance, repairs and maintenance and utilities.
Below is a reconciliation of NOI to net income for the three and nine months ended September 30, 2025 and 2024.
 For the Three Months Ended September 30,For the Nine Months
Ended September 30,
(Amounts in thousands)2025202420252024
NOI$26,731 $29,229 $81,737 $93,764 
Interest and debt expense(14,078)(19,261)(37,673)(51,714)
Interest and other income3,682 6,105 11,555 20,321 
General and administrative(1,349)(1,423)(4,895)(5,058)
Depreciation and amortization(9,018)(7,972)(26,324)(26,146)
Net income$5,968 $6,678 $24,400 $31,167 
v3.25.3
Organization (Details)
Sep. 30, 2025
property
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Number of properties 5
v3.25.3
Revenue Recognition - Schedule of Revenue (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Disaggregation of Revenue [Line Items]        
Lease revenues $ 50,944 $ 53,244 $ 153,172 $ 163,878
Rental revenues 53,424 55,675 159,928 170,464
Parking revenue        
Disaggregation of Revenue [Line Items]        
Revenue from contract with customer 1,214 1,168 3,628 3,483
Tenant services        
Disaggregation of Revenue [Line Items]        
Revenue from contract with customer $ 1,266 $ 1,263 $ 3,128 $ 3,103
v3.25.3
Revenue Recognition - Schedule of Components of Lease Revenue (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Revenue from Contract with Customer [Abstract]        
Fixed lease revenues $ 33,922 $ 35,608 $ 102,285 $ 112,542
Variable lease revenues 17,022 17,636 50,887 51,336
Lease revenues $ 50,944 $ 53,244 $ 153,172 $ 163,878
v3.25.3
Revenue Recognition - Additional Information (Details)
ft² in Thousands
1 Months Ended 3 Months Ended 6 Months Ended 9 Months Ended
Jan. 31, 2025
USD ($)
ft²
Dec. 03, 2022
USD ($)
ft²
May 31, 2024
USD ($)
ft²
Sep. 30, 2025
USD ($)
Sep. 30, 2024
USD ($)
Mar. 31, 2024
USD ($)
Sep. 30, 2025
USD ($)
Sep. 30, 2024
USD ($)
Disaggregation of Revenue [Line Items]                
Rental revenues       $ 53,424,000 $ 55,675,000   $ 159,928,000 $ 170,464,000
Lease revenues       $ 50,944,000 $ 53,244,000   153,172,000 163,878,000
731 Lexington Avenue Property | Home Depot | Tenant Occupant                
Disaggregation of Revenue [Line Items]                
Area of property (in sqft.) | ft² 83              
Lease revenues $ 15,000,000              
Bloomberg | 731 Lexington Avenue Property                
Disaggregation of Revenue [Line Items]                
Area of property (in sqft.) | ft²     947          
Term     11 years          
Payments for lease commissions     $ 32,000,000          
Bloomberg | 731 Lexington Avenue Property | Third Party Broker                
Disaggregation of Revenue [Line Items]                
Payments for lease commissions     26,500,000          
Bloomberg | 731 Lexington Avenue Property | Vornado                
Disaggregation of Revenue [Line Items]                
Payments for lease commissions     $ 5,500,000          
IKEA | Rego Park 1 Property                
Disaggregation of Revenue [Line Items]                
Area of property (in sqft.) | ft²   112            
Payment for termination of lease   $ 10,000,000       $ 10,000,000    
Customer Concentration Risk | Revenue | Bloomberg                
Disaggregation of Revenue [Line Items]                
Rental revenues             $ 96,655,000 $ 93,179,000
Percentage rent contributed by tenant             60.00% 55.00%
v3.25.3
Related Party Transactions - Additional Information (Details)
3 Months Ended 9 Months Ended
May 01, 2024
Apr. 30, 2024
Sep. 30, 2025
USD ($)
Sep. 30, 2024
USD ($)
Sep. 30, 2025
USD ($)
$ / ft²
Sep. 30, 2024
USD ($)
Dec. 31, 2024
USD ($)
Related Party Transaction [Line Items]              
Fees to related party     $ 2,302,000 $ 2,580,000 $ 7,493,000 $ 12,510,000  
Property Management Fees              
Related Party Transaction [Line Items]              
Fees to related party     1,117,000 1,688,000 4,040,000 4,537,000  
Leasing fees              
Related Party Transaction [Line Items]              
Fees to related party     303,000 0 545,000 5,555,000  
Development fees              
Related Party Transaction [Line Items]              
Fees to related party     182,000 $ 192,000 808,000 $ 318,000  
Vornado              
Related Party Transaction [Line Items]              
Management fee agreement value         $ 2,800,000    
Vornado | Property Management Fees | Rego Park II | Retail Space              
Related Party Transaction [Line Items]              
Property management fee, percent fee         2.00%    
Vornado | Property Management Fees | 731 Lexington Avenue Retail | Office and Retail Space              
Related Party Transaction [Line Items]              
Property management fee agreement, price per square foot | $ / ft²         0.50    
Vornado | Property Management Fees | 731 Lexington Avenue Retail | Common Area              
Related Party Transaction [Line Items]              
Property management fee escalation percentage per annum         3.00%    
Vornado | Leasing fees              
Related Party Transaction [Line Items]              
Lease fee percentage of rent one to ten years         3.00%    
Lease fee percentage of rent eleven to twenty years         2.00%    
Lease fee percentage of rent twenty first to thirty years         1.00%    
Percentage increase lease fee if broker used   1.00%          
Percentage of third-party lease commission 33.00%            
Percentage commissions on sale of assets under fifty million         3.00%    
Asset sale commission threshold         $ 50,000,000    
Percentage commissions on sale of assets over fifty million         1.00%    
Vornado | Development fees              
Related Party Transaction [Line Items]              
Development fee as percentage of development costs         6.00%    
Related Party              
Related Party Transaction [Line Items]              
Other Liabilities     499,000   $ 499,000   $ 1,159,000
Related Party | Management And Development Agreement, Base Management Fee | 731 Lexington Avenue Retail | Common Area              
Related Party Transaction [Line Items]              
Fees to related party         387,000    
Related Party | Leasing fees              
Related Party Transaction [Line Items]              
Other Liabilities     182,000   182,000   171,000
Related Party | Development fees              
Related Party Transaction [Line Items]              
Other Liabilities     182,000   182,000   642,000
Related Party | Management, property management, cleaning, engineering and security fees              
Related Party Transaction [Line Items]              
Other Liabilities     $ 135,000   $ 135,000   $ 346,000
Alexander's Inc. | Vornado | Vornado              
Related Party Transaction [Line Items]              
Ownership percentage by noncontrolling owners     32.40%   32.40%    
v3.25.3
Related Party Transactions - Schedule of Fees to Vornado (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Related Party Transaction [Line Items]        
Fees to related party $ 2,302 $ 2,580 $ 7,493 $ 12,510
Company management fees        
Related Party Transaction [Line Items]        
Fees to related party 700 700 2,100 2,100
Development fees        
Related Party Transaction [Line Items]        
Fees to related party 182 192 808 318
Leasing fees        
Related Party Transaction [Line Items]        
Fees to related party 303 0 545 5,555
Property management, cleaning, engineering, parking and security fees        
Related Party Transaction [Line Items]        
Fees to related party $ 1,117 $ 1,688 $ 4,040 $ 4,537
v3.25.3
Mortgages Payable - Schedule of Long-term Debt Instruments (Details) - USD ($)
$ in Thousands
9 Months Ended
Sep. 30, 2025
Dec. 31, 2024
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]    
Notes payable $ 987,100 $ 988,019
Mortgages    
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]    
Deferred debt issuance costs, accumulated amortization 9,766 7,381
Notes payable, gross 993,355 996,544
Deferred debt issuance costs, net of accumulated amortization of $9,766 and $7,381, respectively $ (6,255) (8,525)
Mortgages | 731 Lexington Avenue | Office Space    
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]    
Interest rate 5.04%  
Notes payable, gross $ 400,000 400,000
Mortgages | 731 Lexington Avenue | Retail Space    
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]    
Interest rate 5.76%  
Notes payable, gross $ 300,000 300,000
Basis spread over SOFR 1.51%  
Mortgages | Rego Park II | Retail Space    
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]    
Interest rate 5.60%  
Notes payable, gross $ 199,355 202,544
Mortgages | Rego Park II | Retail Space | SOFR    
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]    
Basis spread over SOFR 1.45%  
Mortgages | Rego Park II | Retail Space | SOFR capped rate    
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]    
Interest cap rate 4.15%  
Mortgages | The Alexander apartment tower | Apartment tower    
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]    
Interest rate 2.63%  
Notes payable, gross $ 94,000 $ 94,000
v3.25.3
Mortgages Payable - Additional Information (Detail) - 731 Lexington Avenue - Mortgages - Retail Space - USD ($)
$ in Millions
9 Months Ended
Aug. 01, 2025
Sep. 30, 2025
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]    
Mortgage loans $ 300 $ 300
Basis spread over SOFR   1.51%
Extension term 60 days  
Interest rate   5.76%
v3.25.3
Stock-Based Compensation (Details) - Director - 2016 Omnibus Stock Plan - Deferred Stock Units - USD ($)
1 Months Ended
May 31, 2025
Sep. 30, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Non option equity instruments granted per director (in shares) 346  
Non option equity instruments market value $ 75,000  
Non option equity instruments grant date fair value per grant 56,250  
Non option equity instruments grant date fair value total $ 394,000  
Non option equity instruments, outstanding, number (in shares)   28,666
Shares available for future grant under the plan (in shares)   477,121
v3.25.3
Fair Value Measurements - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - Recurring - USD ($)
$ in Thousands
Sep. 30, 2025
Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate derivative (included in other assets) $ 4 $ 4,487
Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate derivative (included in other assets) 0 0
Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate derivative (included in other assets) 4 4,487
Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate derivative (included in other assets) $ 0 $ 0
v3.25.3
Fair Value Measurements - Schedule of Interest Rate Derivatives (Details) - USD ($)
$ in Thousands
Sep. 30, 2025
Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Included in other assets $ 4 $ 4,487
Interest rate swap | Designated as Hedging Instrument | 731 Lexington Avenue mortgage loan, retail condominium    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Included in other assets 0 4,117
Interest rate swap | Designated as Hedging Instrument | Rego Park II shopping center mortgage loan    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Included in other assets 4 $ 370
Notional Amount $ 199,355  
Interest cap rate 4.15%  
v3.25.3
Fair Value Measurements - Schedule of Carrying Amount and Fair Value of Financial Instruments (Details) - USD ($)
$ in Thousands
Sep. 30, 2025
Dec. 31, 2024
Level 1 | Carrying Amount    
Assets:    
Cash equivalents $ 67,135 $ 61,889
Level 1 | Fair Value    
Assets:    
Cash equivalents 67,135 61,889
Level 2 | Carrying Amount    
Liabilities:    
Mortgages payable (excluding deferred debt issuance costs, net) 993,355 996,544
Level 2 | Fair Value    
Liabilities:    
Mortgages payable (excluding deferred debt issuance costs, net) $ 983,675 $ 967,941
v3.25.3
Commitments and Contingencies (Details)
9 Months Ended
Sep. 30, 2025
USD ($)
All Risk Property and Rental Value  
Loss Contingencies [Line Items]  
Insurance maximum coverage per incident $ 1,700,000,000
Terrorism Coverage Including NBCR  
Loss Contingencies [Line Items]  
Insurance maximum coverage per incident 1,700,000,000
Insurance maximum coverage in aggregate $ 1,700,000,000
NBCR  
Loss Contingencies [Line Items]  
Federal government responsibility (in percentage) 80.00%
NBCR | FNSIC  
Loss Contingencies [Line Items]  
Insurance deductible $ 348,000
Self insured responsibility (in percentage) 20.00%
General Liability  
Loss Contingencies [Line Items]  
Insurance maximum coverage per property $ 300,000,000
Insurance maximum coverage per incident $ 300,000,000
v3.25.3
Earnings Per Share - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Earnings Per Share [Abstract]        
Net income $ 5,968 $ 6,678 $ 24,400 $ 31,167
Weighted average shares outstanding - basic (in shares) 5,135,956 5,133,534 5,134,705 5,132,043
Weighted average shares outstanding - diluted (in shares) 5,135,956 5,133,534 5,134,705 5,132,043
Net income per common share - basic (in usd per share) $ 1.16 $ 1.30 $ 4.75 $ 6.07
Net income per common share - diluted (in usd per share) $ 1.16 $ 1.30 $ 4.75 $ 6.07
v3.25.3
Segment Information - Narrative (Details)
9 Months Ended
Sep. 30, 2025
segment
Segment Reporting [Abstract]  
Number of reportable segments 1
v3.25.3
Segment Information - Schedule of Summary of NOI (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Segment Reporting Information [Line Items]        
Rental revenues $ 53,424 $ 55,675 $ 159,928 $ 170,464
Total operating expenses (26,693) (26,446) (78,191) (76,700)
Reportable Segment        
Segment Reporting Information [Line Items]        
Rental revenues 53,424 55,675 159,928 170,464
Real estate tax expense (15,755) (15,018) (45,439) (43,931)
Other segment expenses (10,938) (11,428) (32,752) (32,769)
Total operating expenses (26,693) (26,446) (78,191) (76,700)
NOI $ 26,731 $ 29,229 $ 81,737 $ 93,764
v3.25.3
Segment Information - Schedule NOI to Net Income (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Segment Reporting Information [Line Items]        
Interest and debt expense $ (14,078) $ (19,261) $ (37,673) $ (51,714)
Interest and other income 3,682 6,105 11,555 20,321
General and administrative (1,349) (1,423) (4,895) (5,058)
Depreciation and amortization (9,018) (7,972) (26,324) (26,146)
Net income 5,968 6,678 24,400 31,167
Reportable Segment        
Segment Reporting Information [Line Items]        
NOI 26,731 29,229 81,737 93,764
Interest and debt expense (14,078) (19,261) (37,673) (51,714)
Interest and other income 3,682 6,105 11,555 20,321
General and administrative (1,349) (1,423) (4,895) (5,058)
Depreciation and amortization (9,018) (7,972) (26,324) (26,146)
Net income $ 5,968 $ 6,678 $ 24,400 $ 31,167

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