Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 57,632	$ 132,930	$ 41,939
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization, including amortization of debt issuance costs	31,454	34,592	35,121
Straight-lining of rents	7,960	9,817	21,102
Write-off of tenant receivables	0	0	4,122
Stock-based compensation expense	450	450	600
Net gains on sale of real estate (2021 includes $2,348 from discontinued operations)	0	(72,298)	0
Change in fair value of marketable securities	0	(3,482)	8,599
Dividends received in stock	0	0	(214)
Other non-cash adjustments	(2,928)	0	0
Change in operating assets and liabilities:
Tenant and other receivables, net	1,680	1,731	(6,146)
Other assets	2,782	3,099	(28,378)
Amounts due to Vornado	40	(211)	(402)
Accounts payable and accrued expenses	3,141	12,501	2,361
Other liabilities	338	(664)	(638)
Net cash provided by operating activities	102,549	118,465	78,066
CASH FLOWS FROM INVESTING ACTIVITIES
Construction in progress and real estate additions	(14,386)	(19,520)	(32,460)
Purchase of U.S. Treasury bills	(364,238)	0	0
Proceeds from maturities of U.S. Treasury bills	99,358	0	0
Proceeds from sales of real estate	0	81,871	0
Return of short-term investment	0	3,600	0
Proceeds from sale of marketable securities	0	9,506	0
Net cash (used in) provided by investing activities	(279,266)	75,457	(32,460)
CASH FLOWS FROM FINANCING ACTIVITIES
Dividends paid	(92,264)	(92,220)	(92,168)
Debt issuance costs	(46)	(74)	(7,246)
Debt repayments	0	(68,000)	(50,000)
Proceeds from borrowings	0	0	239,708
Net cash (used in) provided by financing activities	(92,310)	(160,294)	90,294
Net (decrease) increase in cash and cash equivalents and restricted cash	(269,027)	33,628	135,900
Cash and cash equivalents and restricted cash at beginning of year	483,505	449,877	313,977
Cash and cash equivalents and restricted cash at end of year	214,478	483,505	449,877
RECONCILIATION OF CASH AND CASH EQUIVALENTS AND RESTRICTED CASH
Cash and cash equivalents at beginning of year	463,539	428,710	298,063
Restricted cash at beginning of year	19,966	21,167	15,914
Cash and cash equivalents and restricted cash at beginning of year	483,505	449,877	313,977
Cash and cash equivalents at end of year	194,933	463,539	428,710
Restricted cash at end of year	19,545	19,966	21,167
Cash and cash equivalents and restricted cash at end of year	214,478	483,505	449,877
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash payments for interest, net of amounts capitalized	25,934	18,568	22,476
NON-CASH TRANSACTIONS
Additional estimated lease liability arising from the recognition of right-of-use asset	16,099	0	0
Liability for real estate additions, including $141 and $489 for development fees due to Vornado in 2021 and 2020, respectively	2,254	1,445	4,955
Write-off of fully amortized and/or depreciated assets	$ 23	$ 5,628	$ 876