CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Total	Total AvalonBay stockholders' equity	Common stock	Additional paid-in capital	Accumulated earnings less dividends	Accumulated other comprehensive loss	Noncontrolling interests
Balance at Dec. 31, 2009	$ 3,050,127	$ 3,050,127	$ 815	$ 3,200,367	$ (149,988)	$ (1,067)
Balance (in shares) at Dec. 31, 2009			81,528,957
Increase (Decrease) in Stockholders' Equity
Net income attributable to common stockholders	176,259	175,331			175,331		928
Unrealized loss on cash flow hedges	(108)	(108)				(108)
Change in redemption value of redeemable noncontrolling interest	(5,573)	(5,573)			(5,573)
Noncontrolling interest consolidation and income allocation	4,045						4,045
Dividends declared to common stockholders	(302,518)	(302,518)			(302,518)
Issuance of common stock, net of withholdings	380,973	380,973	44	380,924	5
Issuance of common stock, net of withholdings (in shares)			4,370,123
Amortization of deferred compensation	12,386	12,386		12,386
Balance at Dec. 31, 2010	3,315,591	3,310,618	859	3,593,677	(282,743)	(1,175)	4,973
Balance (in shares) at Dec. 31, 2010			85,899,080
Increase (Decrease) in Stockholders' Equity
Net income attributable to common stockholders	440,450	441,622			441,622		(1,172)
Unrealized loss on cash flow hedges	(85,845)	(85,845)				(85,845)
Change in redemption value of redeemable noncontrolling interest	(2,607)	(2,607)			(2,607)
Noncontrolling interest consolidation and income allocation	3,350						3,350
Dividends declared to common stockholders	(326,813)	(326,813)			(326,813)
Issuance of common stock, net of withholdings	1,035,302	1,035,302	93	1,036,316	(1,107)
Issuance of common stock, net of withholdings (in shares)			9,276,597
Amortization of deferred compensation	22,464	22,464		22,464
Balance at Dec. 31, 2011	4,401,892	4,394,741	952	4,652,457	(171,648)	(87,020)	7,151
Balance (in shares) at Dec. 31, 2011			95,175,677
Increase (Decrease) in Stockholders' Equity
Net income attributable to common stockholders	423,869	423,869			423,869
Unrealized loss on cash flow hedges	(22,876)	(22,876)				(22,876)
Cash flow hedge losses reclassified to earnings	1,889	1,889				1,889
Change in redemption value of redeemable noncontrolling interest	(375)	(375)			(375)
Noncontrolling interest consolidation and income allocation	(3,573)						(3,573)
Dividends declared to common stockholders	(391,906)	(391,906)			(391,906)
Issuance of common stock, net of withholdings	2,414,775	2,414,775	192	2,416,852	(2,269)
Issuance of common stock, net of withholdings (in shares)			19,227,795
Amortization of deferred compensation	17,098	17,098		17,098
Balance at Dec. 31, 2012	$ 6,840,793	$ 6,837,215	$ 1,144	$ 7,086,407	$ (142,329)	$ (108,007)	$ 3,578
Balance (in shares) at Dec. 31, 2012			114,403,472