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 (loss)	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, 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]
Other comprehensive (loss)	(3,079)
Net (loss) income	1,791
Balance, end of period (in shares) at Jun. 30, 2018		78,748
Balance, end of period at Jun. 30, 2018	639,172	$ 787	141,400	506,769	(9,784)
Balance, beginning of period (in shares) at Mar. 31, 2018		78,546
Balance, beginning of period at Mar. 31, 2018	663,846	$ 785	145,962	519,542	(2,443)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of common stock (in shares)		(171)
Repurchase of common stock	(10,181)	$ (2)	(10,179)
Issuance of common stock for share-based compensation plans (in shares)		358
Issuance of common stock for share-based compensation plans	(11,391)	$ 4	(11,395)
Issuance of common stock under Employee Stock Purchase Plan (in shares)		15
Issuance of common stock under Employee Stock Purchase Plan	849		849
Stock-based compensation	16,163		16,163
Cash dividends declared ($0.12 per share)	(2,364)			(2,364)
Other comprehensive (loss)	(7,341)				(7,341)
Net (loss) income	(10,409)			(10,409)
Balance, end of period (in shares) at Jun. 30, 2018		78,748
Balance, end of period at Jun. 30, 2018	$ 639,172	$ 787	141,400	506,769	(9,784)
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 (loss)	2,001				2,001
Net (loss) income	(28,717)			(28,717)
Balance, end of period (in shares) at Mar. 31, 2019		78,896
Balance, end of period at Mar. 31, 2019	$ 588,429	$ 789	119,182	479,779	(11,321)
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]
Other comprehensive (loss)	1,830
Net (loss) income	$ (61,013)
Balance, end of period (in shares) at Jun. 30, 2019	79,144	79,144
Balance, end of period at Jun. 30, 2019	$ 557,287	$ 791	122,880	445,108	(11,492)
Balance, beginning of period (in shares) at Mar. 31, 2019		78,896
Balance, beginning of period at Mar. 31, 2019	588,429	$ 789	119,182	479,779	(11,321)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of common stock (in shares)		(88)
Repurchase of common stock	(6,302)	$ (1)	(6,301)
Issuance of common stock for share-based compensation plans (in shares)		320
Issuance of common stock for share-based compensation plans	(11,214)	$ 3	(11,217)
Issuance of common stock under Employee Stock Purchase Plan (in shares)		16
Issuance of common stock under Employee Stock Purchase Plan	1,103		1,103
Stock-based compensation	20,113		20,113
Cash dividends declared ($0.12 per share)	(2,375)			(2,375)
Other comprehensive (loss)	(171)				(171)
Net (loss) income	$ (32,296)			(32,296)
Balance, end of period (in shares) at Jun. 30, 2019	79,144	79,144
Balance, end of period at Jun. 30, 2019	$ 557,287	$ 791	$ 122,880	$ 445,108	$ (11,492)