CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY - 6 months ended Jun. 30, 2018 - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Treasury Stock	Comprehensive Income (Loss)	Noncontrolling interest
Balance at Dec. 31, 2017	$ 294,874	$ 142	$ 1,087,582	$ (708,354)	$ (85,085)		$ 589
Balance (in shares) at Dec. 31, 2017		14,218,000			2,239,000
Increase (Decrease) in Stockholders' Equity
Net income and comprehensive income	74,071			74,071		$ 74,071
Non-cash compensation	$ 22,287		22,287
Purchase of treasury stock (in shares)	156,731				157,000
Purchase of treasury stock	$ (46,003)				$ (46,003)
Issuance of common stock for stock options, restricted stock awards and restricted stock units, net of withholding taxes	832	$ 9	823
Issuance of common stock for stock options, restricted stock awards and restricted stock units, net of withholding taxes (in shares)		920,000
Cumulative effect adjustment due to ASU 2014-09	1,373			1,373
Issuance of 0.625% Convertible Senior Notes, net	4		4
Noncontrolling interest	(2)						(2)
Balance at Jun. 30, 2018	$ 347,428	$ 151	$ 1,110,688	$ (632,910)	$ (131,088)		$ 587
Balance (in shares) at Jun. 30, 2018		15,138,000			2,396,000