Condensed Consolidated Statement of Stockholder's Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive (Loss)/Income
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of new accounting standards	$ (23,192)			$ (23,600)	$ 408
Beginning balance, shares at Dec. 31, 2017	80,885	80,885
Beginning balance at Dec. 31, 2017	$ 1,007,876	$ 1	$ 224,455	877,111	(93,691)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	28,287			28,287
Shares issued in connection with share-based compensation, shares		1,151
Shares issued in connection with share-based compensation	15,473		15,473
Payment of tax withholdings related to net share settlements	(10,532)		10,532
Share-based compensation	8,677		8,677
Shares repurchased and retired, shares		(400)
Shares repurchased and retired	(18,479)		(18,479)
Other comprehensive loss	$ (101)				(101)
Ending balance, shares at Mar. 31, 2018	81,636	81,636
Ending balance at Mar. 31, 2018	$ 1,008,009	$ 1	$ 219,594	$ 881,798	$ (93,384)