Consolidated Statements of Equity - USD ($) $ in Thousands		Total	Class A	Common Stock		Common Stock Class A	Common Stock Class B	Additional Paid-In Capital		Cumulative Dividends in Excess of Earnings	Total Stockholders’ Equity	Noncontrolling Interest
Beginning balance (in shares) at Dec. 31, 2012	[1]					50,043,000	57,283,000
Beginning balance at Dec. 31, 2012		$ 1,264,595		$ 1,074	[1]			$ 1,886,909	[1]	$ (633,717)	$ 1,254,266	$ 10,329
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock (in shares)	[1]					10,937,000
Issuance of common stock		239,334		109	[1]			239,225	[1]		239,334
Share-based award transactions, net (in shares)	[1]					211,000	(8,000)
Share-based award transactions, net		5,724		2	[1]			2,469	[1]	76	2,547	3,177
Repurchase and cancellation of common stock (in shares)	[1]					(26,000)
Repurchase and cancellation of common stock		(522)		(1)	[1]			(521)	[1]		(522)
Conversion	[1]					57,275,000	(57,275,000)
Dividends	[1]	(133,984)								(132,680)	(132,680)	(1,304)
Net income (loss)		24,602								24,261	24,261	341
Ending balance (in shares) at Dec. 31, 2013	[1]					118,440,000	0
Ending balance at Dec. 31, 2013		1,399,749		1,184	[1]			2,128,082	[1]	(742,060)	1,387,206	12,543
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock (in shares)						6,371,000
Issuance of common stock		152,014		64				151,950			152,014
Issuance of operating partnership units in connection with acquisitions		16,960										16,960
Share-based award transactions, net (in shares)						263,000
Share-based award transactions, net		4,383		3				4,380			4,383
Repurchase and cancellation of common stock (in shares)						(48,000)
Repurchase and cancellation of common stock		(1,056)		(1)				(1,055)			(1,056)
Redemption of noncontrolling interest and other (in shares)						61,000
Redemption of noncontrolling interest and other		(429)		1				(1,425)			(1,424)	995
Dividends		(141,010)								(139,355)	(139,355)	(1,655)
Net income (loss)		45,810								45,371	45,371	439
Ending balance (in shares) at Dec. 31, 2014			125,087,268			125,087,000
Ending balance at Dec. 31, 2014		1,476,421		1,251				2,281,932		(836,044)	1,447,139	29,282
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock (in shares)						1,800,000
Issuance of common stock		43,649		18				43,631			43,649
Share-based award transactions, net (in shares)						202,000
Share-based award transactions, net		5,724		2				5,722			5,724
Repurchase and cancellation of common stock (in shares)						(62,000)
Repurchase and cancellation of common stock		(1,667)		(1)				(1,666)			(1,667)
Redemption of noncontrolling interest and other		(813)						(813)			(813)
Dividends		(149,801)								(147,539)	(147,539)	(2,262)
Net income (loss)		33,445								32,931	32,931	514
Ending balance (in shares) at Dec. 31, 2015			127,026,839			127,027,000
Ending balance at Dec. 31, 2015		$ 1,406,958		$ 1,270				$ 2,328,806		$ (950,652)	$ 1,379,424	$ 27,534

[1] For the year ended December 31, 2013, amounts have been adjusted retroactively to reflect the Reverse Stock Split effected on December 15, 2014.