Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Accumulated Dividends in Excess of Earnings	Accumulated Other Comprehensive Income (Loss), net	Total Stockholders’ Equity	Noncontrolling Interests in Operating Partnership	Noncontrolling Interests in Consolidated Joint Ventures	Total Noncontrolling Interests
Balance at Beginning of Period at Dec. 31, 2013	$ 3,646,512	$ 694,831	$ 1,279	$ 3,688,937	$ (785,222)	$ 10,691	$ 3,610,516	$ 29,027	$ 6,969	$ 35,996
Balance (shares) at Dec. 31, 2013			128,455,350
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of common units to common stock			$ 1	1,654			1,655	(1,655)		(1,655)
Conversion of common units to common stock (shares)			134,073
Issuance of unvested restricted stock, net of forfeitures (in shares)			124,163
Common stock offering costs	(625)			(625)			(625)
Exercise of stock options	711			711			711
Exercise of stock options (shares)			42,757
Issuance of common stock in exchange for cash and debentures (in shares)			6,869,912
Issuance of common stock in exchange for cash and debentures	266,400		$ 69	266,331			266,400
Issuance of preferred stock, net of offering costs	353,290	353,290					353,290
Amortization of unearned compensation on share-based awards	23,737			23,737			23,737
Reclassification of vested share-based awards				(10,306)			(10,306)	10,306		10,306
Dividends declared on preferred stock	(67,465)				(67,465)		(67,465)
Dividends and distributions on common stock and common and incentive units	(454,204)				(444,103)		(444,103)	(10,101)		(10,101)
Distributions to noncontrolling interests in consolidated joint ventures, net of contributions	(643)								(643)	(643)
Net income (loss)	203,415				200,183		200,183	2,767	465	3,232
Other comprehensive income— foreign currency translation adjustments	(52,373)					(51,312)	(51,312)	(1,061)		(1,061)
Other comprehensive income— fair value of derivatives	(7,936)					(7,775)	(7,775)	(161)		(161)
Other comprehensive income— reclassification of accumulated other comprehensive loss to interest expense	3,419					3,350	3,350	69		69
Balance at End of Period at Dec. 31, 2014	3,914,238	1,048,121	$ 1,349	3,970,439	(1,096,607)	(45,046)	3,878,256	29,191	6,791	35,982
Balance (shares) at Dec. 31, 2014			135,626,255
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of common units to common stock			$ 2	1,841			1,843	(1,843)		(1,843)
Conversion of common units to common stock (shares)			156,008
Issuance of unvested restricted stock, net of forfeitures (in shares)			72,673
Common stock offering costs	799			799			799
Exercise of stock options	896			896			896
Exercise of stock options (shares)			29,311
Issuance of common stock in exchange for cash and debentures (in shares)			10,500,000
Issuance of common stock in exchange for cash and debentures	675,577		$ 105	675,472			675,577
Issuance of preferred stock, net of offering costs	242,014	242,014					242,014
Amortization of unearned compensation on share-based awards	14,375			14,375			14,375
Reclassification of vested share-based awards				(8,602)			(8,602)	8,602		8,602
Dividends declared on preferred stock	(79,423)				(79,423)		(79,423)
Dividends and distributions on common stock and common and incentive units	(480,541)				(470,748)		(470,748)	(9,793)		(9,793)
Distributions to noncontrolling interests in consolidated joint ventures, net of contributions	(493)								(493)	(493)
Net income (loss)	301,591				296,689		296,689	4,442	460	4,902
Other comprehensive income— foreign currency translation adjustments	(51,745)					(50,775)	(50,775)	(970)		(970)
Other comprehensive income— fair value of derivatives	(3,407)					(3,338)	(3,338)	(69)		(69)
Other comprehensive income— reclassification of accumulated other comprehensive loss to interest expense	2,621					2,569	2,569	52		52
Balance at End of Period at Dec. 31, 2015	4,536,502	1,290,135	$ 1,456	4,655,220	(1,350,089)	(96,590)	4,500,132	29,612	6,758	36,370
Balance (shares) at Dec. 31, 2015			146,384,247.000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of common units to common stock			$ 5	5,237			5,242	(5,242)		(5,242)
Conversion of common units to common stock (shares)			430,493
Issuance of unvested restricted stock, net of forfeitures (in shares)			120,082
Exercise of stock options	$ 1,380			1,380			1,380
Exercise of stock options (shares)	33,948		33,948
Issuance of common stock in exchange for cash and debentures (in shares)			12,000,000
Issuance of common stock in exchange for cash and debentures	$ 1,085,444		$ 120	1,085,324			1,085,444
Units issued in connection with employee stock purchase plan	3,349		$ 1	3,348			3,349
Shares issued under employee stock purchase plan (in shares)			50,348
Redemption of series E preferred units	(287,500)	(277,172)			(10,328)		(287,500)
Preferred unit offering costs	(2)	(2)					(2)
Amortization of unearned compensation on share-based awards	24,113			24,113			24,113
Reclassification of vested share-based awards				(10,125)			(10,125)	10,125		10,125
Dividends declared on preferred stock	(83,771)				(83,771)		(83,771)
Dividends and distributions on common stock and common and incentive units	(538,888)				(529,419)		(529,419)	(9,469)		(9,469)
Distributions to noncontrolling interests in consolidated joint ventures, net of contributions	(527)								(527)	(527)
Net income (loss)	431,852				426,187		426,187	5,298	367	5,665
Other comprehensive income— foreign currency translation adjustments	(86,621)					(85,300)	(85,300)	(1,321)		(1,321)
Other comprehensive income— fair value of derivatives	41,998					41,395	41,395	603		603
Other comprehensive income— reclassification of accumulated other comprehensive loss to interest expense	4,968					4,890	4,890	78		78
Balance at End of Period at Dec. 31, 2016	$ 5,132,297	$ 1,012,961	$ 1,582	$ 5,764,497	$ (1,547,420)	$ (135,605)	$ 5,096,015	$ 29,684	$ 6,598	$ 36,282
Balance (shares) at Dec. 31, 2016			159,019,118