Condensed Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Restricted Stock Units	Common stock, par value $0.01 per share	Restricted stock units Restricted Stock Units	Additional paid-in capital	Exchangeable shares of subsidiary	Retained earnings	Retained earnings Cumulative effect of the change in accounting principle related to credit losses	Retained earnings Retained earnings, beginning of the period, as adjusted	Accumulated other comprehensive income (loss)	Treasury stock, at cost, par value $0.01 per share
Beginning Balance at Dec. 31, 2018			$ 450	$ 71,596	$ 846,721	$ 1,958	$ 63,427	$ 0	$ 63,427	$ (35,705)	$ (886,084)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued			18		40,504
Restricted stock units recognized, net of forfeitures				34,311
Restricted stock units delivered				(39,111)
Exchangeable shares of subsidiary delivered						(1,958)
Dividends							(4,042)
Net income (loss)	$ (13,154)						(13,154)
Currency translation adjustment, net of tax										(4,319)
Repurchased		$ (13,700)									(46,262)
Ending Balance at Sep. 30, 2019	$ 28,350		468	66,796	887,225	0	46,231			(40,024)	(932,346)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201602Member
Beginning Balance at Dec. 31, 2018			450	71,596	846,721	1,958	63,427	0	63,427	(35,705)	(886,084)
Ending Balance at Dec. 31, 2019	$ 44,675		468	77,657	887,095	0	69,093	(123)	68,970	(34,115)	(955,523)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Beginning Balance at Jun. 30, 2019			467	56,911	884,646	0	32,645	0	32,645	(35,977)	(915,864)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued			1		2,579
Restricted stock units recognized, net of forfeitures				12,636
Restricted stock units delivered				(2,751)
Exchangeable shares of subsidiary delivered						0
Dividends							(1,343)
Net income (loss)	$ 14,929						14,929
Currency translation adjustment, net of tax										(4,047)
Repurchased											(16,482)
Ending Balance at Sep. 30, 2019	28,350		468	66,796	887,225	0	46,231			(40,024)	(932,346)
Beginning Balance at Dec. 31, 2019	44,675		468	77,657	887,095	0	69,093	(123)	68,970	(34,115)	(955,523)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued			18		48,805
Restricted stock units recognized, net of forfeitures				28,013
Restricted stock units delivered				(49,099)
Exchangeable shares of subsidiary delivered						0
Dividends							(3,859)
Net income (loss)	(31,916)						(31,916)
Currency translation adjustment, net of tax										(50)
Repurchased		$ (14,600)									(23,044)
Ending Balance at Sep. 30, 2020	$ 13,420		486	56,571	935,900	0	33,195			(34,165)	(978,567)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Beginning Balance at Jun. 30, 2020			485	52,257	933,315	0	43,881	$ 0	$ 43,881	(38,325)	(978,145)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued			1		2,585
Restricted stock units recognized, net of forfeitures				7,180
Restricted stock units delivered				(2,866)
Exchangeable shares of subsidiary delivered						0
Dividends							(1,311)
Net income (loss)	$ (9,375)						(9,375)
Currency translation adjustment, net of tax										4,160
Repurchased											(422)
Ending Balance at Sep. 30, 2020	$ 13,420		$ 486	$ 56,571	$ 935,900	$ 0	$ 33,195			$ (34,165)	$ (978,567)