Consolidated Statements of Income (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
REVENUES
Property rentals	$ 33,779	$ 33,514	$ 101,034	$ 100,486
Expense reimbursements	14,863	13,435	41,787	38,202
Total revenues	48,642	46,949	142,821	138,688
EXPENSES
Operating (including fees to Vornado of $1,146, $917, $3,231, and $2,649, respectively)	16,445	14,463	45,184	41,029
Depreciation and amortization	7,225	7,083	21,577	20,931
General and administrative (including management fees to Vornado of $540 and $1,620 in each three and nine-month period)	1,177	1,297	3,895	2,899
Total expenses	24,847	22,843	70,656	64,859
OPERATING INCOME	23,795	24,106	72,165	73,829
Interest and other income, net	41	67	111	217
Interest and debt expense	(11,422)	(9,230)	(34,206)	(32,613)
Income before income taxes	12,414	14,943	38,070	41,433
Income tax (expense) benefit	(4)	(2)	(62)	80
Income from continuing operations	12,410	14,941	38,008	41,513
Income from discontinued operations	6,938	7,327	20,002	18,762
Net income	19,348	22,268	58,010	60,275
Net income attributable to the noncontrolling interest	(492)	(1,843)	(780)	(1,486)
Net income attributable to Alexander's	$ 18,856	$ 20,425	$ 57,230	$ 58,789
Net income per common share - basic
Income from continuing operations - basic (in dollars per share)	$ 2.43	$ 2.93	$ 7.44	$ 8.13
Income from discontinued operations, net - basic (in dollars per share)	$ 1.26	$ 1.07	$ 3.76	$ 3.38
Net income per common share - basic (in dollars per share)	$ 3.69	$ 4.00	$ 11.20	$ 11.51
Weighted average shares outstanding - basic (in shares)	5,108,016	5,106,984	5,107,474	5,106,427
Net income per common share - diluted
Income from continuing operations - diluted (in dollars per share)	$ 2.43	$ 2.93	$ 7.44	$ 8.13
Income from discontinued operations, net - diluted (in dollars per share)	$ 1.26	$ 1.07	$ 3.76	$ 3.38
Net income per common share - diluted (in dollars per share)	$ 3.69	$ 4.00	$ 11.20	$ 11.51
Weighted average shares outstanding - diluted (in shares)	5,108,016	5,106,984	5,107,474	5,106,427
Dividends per common share	$ 3.75	$ 3.00	$ 11.25	$ 9.00