Condensed Consolidated Statements of Changes in Shareholders' (Deficit) Equity - USD ($) $ in Thousands	Preferred Stock	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained (Deficit)	Accumulated Other Comprehensive (Loss)	Total
Balance at Dec. 31, 2015		$ 830	$ (28,414)	$ 988,686	$ (1,634,591)	$ (4,554)	$ (678,043)
Balance (in shares) at Dec. 31, 2015	8,624	80,889,275
Increase (Decrease) in Shareholders' Deficit
Share-based compensation arrangements, net of tax benefits of $8,510 for the period ended September 30, 2016		$ 8		18,835			18,843
Share-based compensation arrangements (in shares)		859,560
Foreign currency translation adjustment						1,060	1,060
Conversion of preferred stock		$ 17		(17)
Conversion of preferred stock (in shares)	(1,693)	1,693,000
Net income					104,278		104,278
Balance at Sep. 30, 2016		$ 855	(28,414)	1,007,504	(1,530,313)	(3,494)	(553,862)
Balance (in shares) at Sep. 30, 2016	6,931	83,441,835
Balance at Dec. 31, 2016		$ 932	(28,414)	1,014,119	(1,525,281)	(4,676)	(543,320)
Balance (in shares) at Dec. 31, 2016		91,122,308
Increase (Decrease) in Shareholders' Deficit
Repurchase of Preferred Stock		$ (13)		(24,783)			(24,796)
Repurchase of Preferred Stock (in shares)		(1,264,149)
Share-based compensation arrangements, net of tax benefits of $8,510 for the period ended September 30, 2016		$ 10		13,104			13,114
Share-based compensation arrangements (in shares)		1,028,349
Foreign currency translation adjustment						3,491	3,491
Net income					811,523		811,523
Balance at Sep. 30, 2017		$ 929	$ (28,414)	$ 1,002,440	$ (713,758)	$ (1,185)	$ 260,012
Balance (in shares) at Sep. 30, 2017		90,886,508