Significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2011

Accounting Policies [Abstract]

Reconciliation Of Net Income Attributable To Common Stockholders To Estimated Taxable Income [Table Text Block]

(Unaudited and in thousands)	Years Ended December 31,
	2011		2010		2009
Net income attributable to Alexander’s	$	79,423	$	66,429	$	132,190
Straight-line rent adjustments		(12,609)		(15,182)		(23,381)
Depreciation and amortization timing differences		1,263		602		1,385
Reversal of liability for income taxes		-		(3,162)		(37,307)
Interest expense		(2,425)		-		(107)
Stock appreciation rights compensation expense		-		-		(57,113)
Other		(3,429)		6,245		(3,395)
Taxable income before net operating loss ("NOL")		62,223		54,932		12,272
NOL carried forward		-		(16,939)		(29,211)
Estimated taxable income/(loss)	$	62,223	$	37,993	$	(16,939)