Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning Balance at Dec. 31, 2013	$ 757,695	$ 505	$ 1,228,845	$ (7,766)	$ (454,770)	$ (9,119)
Net income	126,452				126,452
Other comprehensive income (loss), net of income taxes	(17,212)					(17,212)
Repurchase and conversion of convertible notes	(54,322)		(51,996)		(2,326)
Repurchase of common stock warrants	(307,491)		(304,400)		(3,091)
Payment of dividend	(112,772)		692	(236)	(113,228)
Exercise of stock options	6,862	3	6,859
Net tax benefit related to stock based compensation	(302)		(302)
Restricted stock units and stock options surrendered	(3,276)	2	(3,278)
Stock-based compensation expense	5,773		5,773
Ending Balance at Dec. 31, 2014	401,407	510	882,193	(8,002)	(446,963)	(26,331)
Net income	111,511				111,511
Other comprehensive income (loss), net of income taxes	1,284					1,284
Payment of dividend	(139,041)		910	(1,999)	(137,952)
Exercise of stock options	1,777	1	1,776
Net tax benefit related to stock based compensation	(2)		(2)
Restricted stock units and stock options surrendered	(3,532)	2	(3,534)
Stock-based compensation expense	6,158		6,158
Ending Balance at Dec. 31, 2015	379,562	513	887,501	(10,001)	(473,404)	(25,047)
Net income	159,366				159,366
Other comprehensive income (loss), net of income taxes	2,779					2,779
Repurchase of Company stock for retirement	(24,811)	(5)			(24,806)
Payment of dividend	(153,694)		883	(1,541)	(153,036)
Exercise of stock options	1,702		1,702
Restricted stock units and stock options surrendered	(3,110)	2	(3,112)
Stock-based compensation expense	6,128		6,128
Ending Balance at Dec. 31, 2016	367,997	$ 510	$ 893,102	$ (11,542)	(491,805)	$ (22,268)
Tax benefit related to adoption of ASU 2016-09	$ 75				$ 75