UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive (Loss) Income
Balance, beginning of period (in shares) at Dec. 31, 2017		78,081
Balance, beginning of period at Dec. 31, 2017	$ 655,870	$ 781	$ 152,097	$ 509,697	$ (6,705)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of common stock (in shares)		(101)
Repurchase of common stock	(5,689)	$ (1)	(5,688)
Issuance of common stock for share-based compensation plans (in shares)		566
Issuance of common stock for share-based compensation plans	(15,551)	$ 5	(15,556)
Stock-based compensation	15,109		15,109
Cash dividends declared ($0.12 per share)	(2,355)			(2,355)
Other comprehensive income	4,262				4,262
Net (loss) income	12,200			12,200
Balance, end of period (in shares) at Mar. 31, 2018		78,546
Balance, end of period at Mar. 31, 2018	$ 663,846	$ 785	145,962	519,542	(2,443)
Balance, beginning of period (in shares) at Dec. 31, 2018	78,526	78,526
Balance, beginning of period at Dec. 31, 2018	$ 621,531	$ 785	123,205	510,863	(13,322)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of common stock (in shares)		(144)
Repurchase of common stock	(7,587)	$ (1)	(7,586)
Issuance of common stock for share-based compensation plans (in shares)		514
Issuance of common stock for share-based compensation plans	(14,838)	$ 5	(14,843)
Stock-based compensation	18,406		18,406
Cash dividends declared ($0.12 per share)	(2,367)			(2,367)
Other comprehensive income	2,001				2,001
Net (loss) income	$ (28,717)			(28,717)
Balance, end of period (in shares) at Mar. 31, 2019	78,896	78,896
Balance, end of period at Mar. 31, 2019	$ 588,429	$ 789	$ 119,182	$ 479,779	$ (11,321)