Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 102,413	$ 57,632	$ 132,930
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization, including amortization of debt issuance costs	34,605	31,454	34,592
Net gains on sale of real estate (2021 includes $2,348 from discontinued operations)	(53,952)	0	(72,298)
Straight-lining of rents	2,631	7,960	9,817
Stock-based compensation expense	450	450	450
Change in fair value of marketable securities	0	0	(3,482)
Interest rate cap premium amortization	7,770	0	0
Other non-cash adjustments	(1,559)	(2,928)	0
Change in operating assets and liabilities:
Tenant and other receivables	(572)	1,680	1,731
Other assets	14,141	2,782	3,099
Amounts due to Vornado	(60)	40	(211)
Accounts payable and accrued expenses	3,263	3,141	12,501
Other liabilities	(19)	338	(664)
Net cash provided by operating activities	109,111	102,549	118,465
CASH FLOWS FROM INVESTING ACTIVITIES
Construction in progress and real estate additions	(4,681)	(14,386)	(19,520)
Purchase of U.S. Treasury bills	0	(364,238)	0
Proceeds from maturities of U.S. Treasury bills	264,881	99,358	0
Proceeds from sales of real estate	67,821	0	81,871
Purchase of interest rate cap	(11,258)	0	0
Proceeds from interest rate cap	5,049	0	0
Return of short-term investment	0	0	3,600
Proceeds from sale of marketable securities	0	0	9,506
Net cash provided by (used in) investing activities	321,812	(279,266)	75,457
CASH FLOWS FROM FINANCING ACTIVITIES
Dividends paid	(92,320)	(92,264)	(92,220)
Debt issuance costs	(104)	(46)	(74)
Debt repayments	0	0	(68,000)
Net cash used in financing activities	(92,424)	(92,310)	(160,294)
Net increase (decrease) in cash and cash equivalents and restricted cash	338,499	(269,027)	33,628
Cash and cash equivalents and restricted cash at beginning of year	214,478	483,505	449,877
Cash and cash equivalents and restricted cash at end of year	552,977	214,478	483,505
RECONCILIATION OF CASH AND CASH EQUIVALENTS AND RESTRICTED CASH
Cash and cash equivalents at beginning of year	194,933	463,539	428,710
Restricted cash at beginning of year	19,545	19,966	21,167
Cash and cash equivalents and restricted cash at beginning of year	214,478	483,505	449,877
Cash and cash equivalents at end of year	531,855	194,933	463,539
Restricted cash at end of year	21,122	19,545	19,966
Cash and cash equivalents and restricted cash at end of year	552,977	214,478	483,505
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash payments for interest (net of amounts capitalized)	53,975	25,934	18,568
NON-CASH TRANSACTIONS
Write-off of fully depreciated assets	8,097	23	5,628
Liability for real estate additions, including $141 for development fees due to Vornado in 2021	1,969	2,254	1,445
Additional estimated lease liability arising from the recognition of right-of-use asset	$ 0	$ 16,099	$ 0