Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Real estate, at cost:
Land	$ 74,974	$ 74,974
Buildings and leasehold improvements	985,637	934,782
Development and construction in progress	1,597	40,535
Total	1,062,208	1,050,291
Accumulated depreciation and amortization	(184,873)	(157,232)
Real estate, net	877,335	893,059
Cash and cash equivalents	506,619	397,220
Short-term investments	5,000	23,000
Restricted cash	88,769	85,567
Accounts receivable, net of allowance for doubtful accounts of $1,039 and $1,047, respectively	2,552	4,224
Receivable arising from the straight-lining of rents	188,289	175,680
Deferred lease and other property costs, net (including unamortized leasing fees to Vornado of $48,776 and $48,949, respectively)	66,237	68,835
Deferred debt issuance costs, net of accumulated amortization of $15,111 and $18,855, respectively	11,254	8,167
Other assets	25,252	23,548
Total assets	1,771,307	1,679,300
Liabilities and Equity
Notes and mortgages payable	1,330,932	1,246,411
Amounts due to Vornado	41,340	43,785
Accounts payable and accrued expenses	34,577	41,610
Other liabilities	1,213	3,718
Total liabilities	1,408,062	1,335,524
Commitments and contingencies
Preferred stock: $1.00 par value per share; authorized, 3,000,000 shares; issued and outstanding, none
Common stock: $1.00 par value per share; authorized, 10,000,000 shares; issued, 5,173,450 shares; outstanding, 5,105,936 shares	5,173	5,173
Additional capital	31,801	31,501
Retained earnings	322,201	304,055
Alexander's equity before treasury stock	359,175	340,729
Treasury stock: 67,514 shares, at cost	(375)	(375)
Total Alexander's equity	358,800	340,354
Noncontrolling interest in consolidated subsidiary	4,445	3,422
Total equity	363,245	343,776
Total liabilities and equity	$ 1,771,307	$ 1,679,300