Consolidated Statements of Equity (USD $) In Thousands, except Share data, unless otherwise specified		Total		Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Distributions in Excess of Accumulated Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interest [Member]
Balances at Dec. 31, 2011		$ 1,553,728		$ 73,750	$ 3	$ 1,844,611	$ (408,066)	$ (72,771)	$ 116,201
Balances (in shares) at Dec. 31, 2011				2,950,000	33,888,000
Net income		139,590					125,284		14,306
Reversal of unrealized gains upon the sale of marketable securities		(1,082)						(1,018)	(64)
Changes in fair value of cash flow hedges and reclassification to interest expense		3,402						3,183	219
Changes in fair value of marketable securities		1,411						1,345	66
Issuance of common stock under:
Stock option plans		4,675				4,675
Stock option plans (in shares)					151,000
Sale of common stock		357,720				357,720
Sale of common stock (in shares)					2,404,000
Equity based compensation costs		1,801				(430)			2,231
Contributions from noncontrolling interest		4,232							4,232
Redemptions of noncontrolling interest		(6,986)				(1,798)			(5,188)
Distributions to noncontrolling interest		(16,691)							(16,691)
Contributions from noncontrolling interest	[1]	0
Retirement of noncontrolling interest	[1]	0
Common and preferred stock dividends declared		(161,684)					(161,684)
Balances at Dec. 31, 2012		1,880,116		73,750	3	2,204,778	(444,466)	(69,261)	115,312
Balances (in shares) at Dec. 31, 2012				2,950,000	36,443,000
Net income		172,055					156,283		15,772
Reversal of unrealized gains upon the sale of marketable securities		(1,767)						(1,673)	(94)
Changes in fair value of cash flow hedges and reclassification to interest expense		12,614						11,934	680
Changes in fair value of marketable securities		(1,556)						(1,472)	(84)
Issuance of common stock under:
Stock option plans		7,244				7,244
Stock option plans (in shares)					65,000
Sale of common stock		138,366			1	138,365
Sale of common stock (in shares)					913,000
Equity based compensation costs		1,608				(907)			2,515
Redemptions of noncontrolling interest		(5,711)				(3,717)			(1,994)
Distributions to noncontrolling interest		(18,488)							(18,488)
Contributions from noncontrolling interest	[1]	0
Retirement of noncontrolling interest	[1]	0
Common and preferred stock dividends declared		(186,243)					(186,243)
Balances at Dec. 31, 2013		1,998,238		73,750	4	2,345,763	(474,426)	(60,472)	113,619
Balances (in shares) at Dec. 31, 2013				2,950,000	37,421,000
Net income		134,438					122,150		12,288
Reversal of unrealized gains upon the sale of marketable securities		(886)						(841)	(45)
Changes in fair value of cash flow hedges and reclassification to interest expense		4,168						3,721	447
Changes in fair value of marketable securities		6,302						6,140	162
Issuance of common stock under:
Stock option plans		3,774,087			2	3,774,085
Stock option plans (in shares)					23,067,000
Stock Option And Restricted Stock Plans		11,024				11,024
Stock Option And Restricted Stock Plans (in shares)					218,000
Sale of common stock		532,670				532,670
Sale of common stock (in shares)					2,943,000
Equity based compensation costs		11,872				5,719			6,153
Redemptions of noncontrolling interest		4,026				(2,934)			(1,092)
Distributions to noncontrolling interest		17,069							(17,069)
Reclassification of noncontrolling interest to redeemable noncontrolling interest		(20,890)				(19,823)			(1,067)
Changes in the redemption value of redeemable noncontrolling interest		312				312
Conversion of Series G preferred stock		4,349				4,349
Conversion of Series G preferred stock (in shares)					34,000
Contributions from noncontrolling interest		1,419,816	[1]						(1,419,816)
Retirement of noncontrolling interest		(1,419,816)	[1]						1,419,816
Common and preferred stock dividends declared		298,521					(298,521)
Balances at Dec. 31, 2014		$ 6,136,068		$ 73,750	$ 6	$ 6,651,165	$ (650,797)	$ (51,452)	$ 113,396
Balances (in shares) at Dec. 31, 2014				2,950,000	63,683,000

[1] See note 2(r) for details of noncash investing and financing activities related to the BRE merger.