Condensed Consolidated Statements of Shareholders' Deficit (unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive (Loss) Income	Distributions in Excess of Accumulated Earnings	Noncontrolling Interest
Beginning balance, value at Dec. 31, 2017	$ (1,207,142)	$ 17	$ 644,328	$ 7,821	$ (1,960,715)	$ 101,407
Beginning balance, shares at Dec. 31, 2017		174,851,514
Impact of change in accounting standard, net of tax	1,859				1,859
Net income (loss)	(2,362)				(2,293)	(69)
Amortization of discount on convertible preferred stock	(1,490)		(1,490)
Other comprehensive income (loss)	49,559			48,416		1,143
Common stock dividends declared	(211,486)				(211,486)
Distributions to noncontrolling interest	(4,958)					(4,958)
Convertible preferred stock dividends	(1,312)				(1,312)
Net share settlement	(1,575)		(1,306)		(269)
Stock-based compensation	4,095		4,095
Stock-based compensation, shares		177,321
Ending balance, value at Jun. 30, 2018	(1,374,812)	$ 17	645,627	56,237	(2,174,216)	97,523
Ending balance, shares at Jun. 30, 2018		175,028,835
Beginning balance, value at Mar. 31, 2018	(1,271,617)	$ 17	645,403	46,735	(2,063,640)	99,868
Beginning balance, shares at Mar. 31, 2018		174,969,646
Net income (loss)	(3,593)				(3,503)	(90)
Amortization of discount on convertible preferred stock	(745)		(745)
Other comprehensive income (loss)	9,726			9,502		224
Common stock dividends declared	(106,417)				(106,417)
Distributions to noncontrolling interest	(2,479)					(2,479)
Convertible preferred stock dividends	(656)				(656)
Net share settlement	(916)		(916)
Stock-based compensation	1,885		1,885
Stock-based compensation, shares		59,189
Ending balance, value at Jun. 30, 2018	(1,374,812)	$ 17	645,627	56,237	(2,174,216)	97,523
Ending balance, shares at Jun. 30, 2018		175,028,835
Beginning balance, value at Dec. 31, 2018	(1,493,203)	$ 18	757,517	30,105	(2,373,218)	92,375
Beginning balance, shares at Dec. 31, 2018		180,535,971
Impact of change in accounting standard, net of tax	(63,222)				(63,222)
Net income (loss)	42,039				41,159	880
At-the-market issuance of common stock, net of offering costs	21,641		21,641
At-the-market issuance of common stock, net of offering, shares		1,176,186
Amortization of discount on convertible preferred stock	(993)		(993)
Other comprehensive income (loss)	(50,112)			(49,065)		(1,047)
Common stock dividends declared	(17,170)				(17,170)
Distributions to noncontrolling interest	(394)					(394)
Exchange of noncontrolling interest			4,260			(4,260)
Exchange of noncontrolling interest, shares		390,788
Convertible preferred stock dividends	(875)				(875)
Net share settlement	(1,765)		(1,765)
Stock-based compensation	5,085		5,085
Stock-based compensation, shares		340,627
Equity settled contingent consideration	11,178		11,178
Equity settled contingent consideration, in shares		645,385
Deferred tax liability related to exchangeable note issuance	(3,499)		(3,499)
Issuance of common stock - employee stock purchase plan	447		447
Issuance of common stock - employee stock purchase plan, in shares		33,800
Equity component value of exchangeable note issuance, net	80,770		80,770
Sale of common stock warrant	50,819		50,819
Payment for bond hedge option	(70,035)		(70,035)
Ending balance, value at Jun. 30, 2019	(1,489,289)	$ 18	855,425	(18,960)	(2,413,326)	87,554
Ending balance, shares at Jun. 30, 2019		183,122,757
Beginning balance, value at Mar. 31, 2019	(1,550,782)	$ 18	790,347	9,661	(2,442,564)	91,756
Beginning balance, shares at Mar. 31, 2019		182,670,494
Impact of change in accounting standard, net of tax	(112)				(112)
Net income (loss)	39,547				38,717	830
Amortization of discount on convertible preferred stock	(248)		(248)
Other comprehensive income (loss)	(29,206)			(28,621)		(585)
Common stock dividends declared	(9,148)				(9,148)
Distributions to noncontrolling interest	(187)					(187)
Exchange of noncontrolling interest			4,260			(4,260)
Exchange of noncontrolling interest, shares		390,788
Convertible preferred stock dividends	(219)				(219)
Net share settlement	(186)		(186)
Stock-based compensation	3,197		3,197
Stock-based compensation, shares		61,475
Deferred tax liability related to exchangeable note issuance	(3,499)		(3,499)
Equity component value of exchangeable note issuance, net	80,770		80,770
Sale of common stock warrant	50,819		50,819
Payment for bond hedge option	(70,035)		(70,035)
Ending balance, value at Jun. 30, 2019	$ (1,489,289)	$ 18	$ 855,425	$ (18,960)	$ (2,413,326)	$ 87,554
Ending balance, shares at Jun. 30, 2019		183,122,757