Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 674,993	$ 81,046	$ 67,445
Adjustments to reconcile net income to net cash provided by operating activities:
Net gain on sale of real estate	(599,628)	0	0
Depreciation and amortization, including amortization of debt issuance costs	36,363	37,086	34,849
Straight-lining of rental income	(4,475)	(12,609)	(15,182)
Stock-based compensation expense	300	300	0
Reversal of income tax liability	0	(2,561)	(5,113)
Other non-cash adjustments	0	0	1,238
Changes in operating assets and liabilities:
Tenant and other receivables, net	234	1,672	(2,065)
Other assets	4,318	(5,484)	(6,068)
Amounts due to Vornado	(2,405)	(2,445)	(12,881)
Accounts payable and accrued expenses	(107)	(4,547)	13,273
Income tax liability of taxable REIT subsidiary	29	87	704
Other liabilities	85	(31)	(178)
Net cash provided by operating activities	109,707	92,514	76,022
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds from sale of real estate	714,054	0	0
Construction in progress and real estate additions	(7,351)	(14,415)	(42,310)
Proceeds from maturing short-term investments	5,000	23,000	40,000
Restricted cash	(1,626)	(3,202)	5,917
Purchases of short-term investments	0	(5,000)	(23,000)
Net cash provided by (used in) investing activities	710,077	383	(19,393)
CASH FLOWS FROM FINANCING ACTIVITIES
Dividends paid, including a special dividend of $623,178, or $122.00 per share in 2012	(699,791)	(61,277)	(38,295)
Debt repayments	(265,016)	(508,479)	(68,619)
Acquisition of the noncontrolling interest	(7,800)	0	0
Debt issuance costs	(400)	(6,142)	(57)
Proceeds from borrowing	0	593,000	34,828
Distributions to the noncontrolling interest	0	(600)	0
Net cash (used in) provided by financing activities	(973,007)	16,502	(72,143)
Net (decrease) increase in cash and cash equivalents	(153,223)	109,399	(15,514)
Cash and cash equivalents at beginning of year	506,619	397,220	412,734
Cash and cash equivalents at end of year	353,396	506,619	397,220
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash payments for interest, of which $1,269 was capitalized in 2010	47,932	53,343	52,889
NON-CASH TRANSACTIONS
Marketable securities received in connection with the sale of real estate	30,000	0	0
Commission payable incurred in connection with the sale of real estate	7,510	0	0
Change in unrealized net gain on securities available-for-sale	1,206	0	0
Write-off of fully amortized and/or depreciated assets	648	6,799	0
Non-cash additions to real estate included in accounts payable and accrued expenses	$ 221	$ 3,052	$ 0