CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - USD ($) $ in Thousands	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in-Capital [Member]	Accumulated Distributions in Excess of Net Income [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Non-controlling Interests [Member]	LCIF [Member]
Beginning balance at Dec. 31, 2013	$ 1,539,483	$ 94,016	$ 23	$ 2,717,787	$ (1,300,527)	$ 4,439	$ 23,745
Beginning balance (in shares) at Dec. 31, 2013		1,935,400	228,663,022
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Redemption of noncontrolling OP units for common shares	(1,962)			(858)			(1,104)
Redemption of noncontrolling OP units for common shares (in shares)			29,086
Issuance of common shares upon conversion of convertible notes	14,347			14,347
Issuance of common shares upon conversion of Convertible Notes (in shares)			1,904,542
Exercise of employee common share options	597			597
Exercise of employee common share options, net (in shares)			303,852
Issuance of common shares and deferred compensation amortization, net	31,558			31,558
Issuance of common shares and deferred compensation amortization, net (in shares)			2,391,193
Acquisition of consolidated joint venture partner's equity interest	(2,100)				(2,262)		162
Forfeiture of employee common shares	(57)			(57)
Forfeiture of employee common shares (in shares)			(13,658)
Dividends/distributions	(166,374)				(162,366)		(4,008)
Net Income	97,463				93,104		4,359	$ 59,549
Other comprehensive income	(4,035)					(4,035)
Ending balance at Dec. 31, 2014	1,508,920	$ 94,016	$ 23	2,763,374	(1,372,051)	404	23,154
Ending balance (in shares) at Dec. 31, 2014		1,935,400	233,278,037
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Redemption of noncontrolling OP units for common shares				165			(165)
Redemption of noncontrolling OP units for common shares (in shares)			32,780
Repurchase of common shares	(18,431)			(18,431)
Repurchase of common shares (in shares)			(2,216,799)
Issuance of common shares upon conversion of convertible notes	3,630			3,630
Issuance of common shares upon conversion of Convertible Notes (in shares)			519,664
Issuance of common shares and deferred compensation amortization, net	28,099			28,099
Issuance of common shares and deferred compensation amortization, net (in shares)			2,961,543
Acquisition of consolidated joint venture partner's equity interest	(1,234)				(1,247)		13
Dividends/distributions	(171,001)				(167,313)		(3,688)
Net Income	114,891				111,703		3,188	42,315
Other comprehensive income	(2,343)					(2,343)
Ending balance at Dec. 31, 2015	1,462,531	$ 94,016	$ 23	2,776,837	(1,428,908)	(1,939)	22,502
Ending balance (in shares) at Dec. 31, 2015		1,935,400	234,575,225
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Redemption of noncontrolling OP units for common shares				210			(210)
Redemption of noncontrolling OP units for common shares (in shares)			48,549
Repurchase of common shares	(8,973)			(8,973)
Repurchase of common shares (in shares)			(1,184,113)
Issuance of common shares upon conversion of convertible notes	12,027			12,027
Issuance of common shares upon conversion of Convertible Notes (in shares)			1,892,269
Exercise of employee common share options	(1,101)			(1,101)
Exercise of employee common share options, net (in shares)			170,412
Issuance of common shares and deferred compensation amortization, net	21,737		$ 1	21,736
Issuance of common shares and deferred compensation amortization, net (in shares)			2,534,835
Dividends/distributions	(171,086)				(167,682)		(3,404)
Net Income	96,450				95,624		826	$ (3,921)
Other comprehensive income	906					906
Ending balance at Dec. 31, 2016	$ 1,412,491	$ 94,016	$ 24	$ 2,800,736	$ (1,500,966)	$ (1,033)	$ 19,714
Ending balance (in shares) at Dec. 31, 2016		1,935,400	238,037,177