CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Series E Cumulative Redeemable Preferred Stock Preferred Stock	Series E Cumulative Redeemable Preferred Stock Cumulative dividends and distributions	Series E Cumulative Redeemable Preferred Stock	Series F Cumulative Redeemable Preferred Stock Preferred Stock	Series F Cumulative Redeemable Preferred Stock Cumulative dividends and distributions	Series F Cumulative Redeemable Preferred Stock	Common Stock	Additional Paid In Capital	Retained Earnings	Cumulative dividends and distributions	Noncontrolling Interest in Consolidated Joint Venture	Total
Beginning Balance at Dec. 31, 2016	$ 115,000			$ 75,000			$ 2,201	$ 2,596,620	$ 786,901	$ (1,092,952)	$ 49,062	$ 2,531,832
Beginning Balance (in shares) at Dec. 31, 2016	4,600,000			3,000,000			220,073,140
Increase (Decrease) in Stockholders' Equity
Amortization of deferred stock compensation								8,514				8,514
Issuance of restricted common stock, net							$ 4	(3,797)				(3,793)
Issuance of restricted common stock, net (in shares)							404,963
Forfeiture of restricted common stock (in shares)							(33,298)
Common stock distributions and distributions payable										(164,231)		(164,231)
Preferred stock dividends and dividends payable		$ (7,993)	$ (7,993)		$ (4,837)	$ (4,837)
Distributions to noncontrolling interest											(8,250)	(8,250)
Net proceeds from sale of common stock							$ 48	77,884				77,932
Number of shares of common stock sold (in shares)							4,876,855
Net income									145,376		7,628	153,004
Ending Balance at Dec. 31, 2017	$ 115,000			$ 75,000			$ 2,253	2,679,221	932,277	(1,270,013)	48,440	2,582,178
Ending Balance (in shares) at Dec. 31, 2017	4,600,000			3,000,000			225,321,660
Increase (Decrease) in Stockholders' Equity
Amortization of deferred stock compensation								9,383				9,383
Issuance of restricted common stock, net							$ 4	(4,236)				(4,232)
Issuance of restricted common stock, net (in shares)							346,526
Forfeiture of restricted common stock							$ (1)	1
Forfeiture of restricted common stock (in shares)							(12,793)
Common stock distributions and distributions payable										(157,359)		(157,359)
Preferred stock dividends and dividends payable		(7,992)	(7,992)		(4,838)	(4,838)
Distributions to noncontrolling interest											(9,369)	(9,369)
Net proceeds from sale of common stock							$ 26	44,315				44,341
Number of shares of common stock sold (in shares)							2,590,854
Net income									250,445		8,614	259,059
Ending Balance at Dec. 31, 2018	$ 115,000			$ 75,000			$ 2,282	2,728,684	1,182,722	(1,440,202)	47,685	2,711,171
Ending Balance (in shares) at Dec. 31, 2018	4,600,000			3,000,000			228,246,247
Increase (Decrease) in Stockholders' Equity
Amortization of deferred stock compensation								9,719				9,719
Issuance of restricted common stock, net							$ 4	(4,439)				(4,435)
Issuance of restricted common stock, net (in shares)							396,972
Forfeiture of restricted common stock (in shares)							(3,932)
Common stock distributions and distributions payable										(166,747)		(166,747)
Preferred stock dividends and dividends payable		$ (7,993)	$ (7,993)		$ (4,837)	$ (4,837)
Distributions to noncontrolling interest											(8,512)	(8,512)
Repurchase of outstanding common stock							$ (37)	(50,051)				(50,088)
Repurchase of outstanding common stock (in shares)							(3,783,936)
Net income									135,733		7,060	142,793
Ending Balance at Dec. 31, 2019	$ 115,000			$ 75,000			$ 2,249	$ 2,683,913	$ 1,318,455	$ (1,619,779)	$ 46,233	$ 2,621,071
Ending Balance (in shares) at Dec. 31, 2019	4,600,000			3,000,000			224,855,351