Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Preferred Shares	Common Shares	Additional Paid-in Capital	Accumulated Deficit	Treasury Shares	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest
Balance at Dec. 31, 2016	$ 475,990	$ 0	$ 0	$ 1,311,226	$ (472,764)	$ (65)	$ (362,930)	$ 523
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(105,254)				(105,713)			459
Currency translation adjustment	35,038						34,717	321
Dividends paid	(1,186)							(1,186)
Cumulative effect of implementation of ASU 2016-09				636	(636)
Issuance of shares for acquisitions	64,734			64,734
Share-based compensation	7,045			7,338		(293)
Balance at Dec. 31, 2017	476,367	0	0	1,383,934	(579,113)	(358)	(328,213)	117
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(81,847)				(82,243)			396
Currency translation adjustment	(43,036)						(43,036)
Dividends paid	(513)							(513)
Issuance of shares for acquisitions	173,854	6,972		166,882
Dividends attributable to Class A preferred shares	(49,589)	49,308		281	(49,589)
Share-based compensation	10,205			11,036		(831)
Balance at Dec. 31, 2018	535,424	56,280	0	1,562,133	(710,551)	(1,189)	(371,249)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of implementation of ASU 2014-09	(699)				(699)
Net income (loss)	(58,334)				(58,491)			157
Currency translation adjustment	8,076						8,076
Dividends paid	(182)							(182)
Dividends attributable to Class A preferred shares	(1,849)	1,849			(1,849)
Acquisition of noncontrolling interest	687							687
Share-based compensation	5,833			10,116		(4,283)
Balance at Dec. 31, 2019	$ 490,805	$ 58,129	$ 0	$ 1,572,249	$ (771,590)	$ (5,472)	$ (363,173)	$ 662