Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands		Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2017		$ 179,189	$ 0	$ 179,448	$ (259)
Balance, shares at Dec. 31, 2017			30,305
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income		8,059		8,059
Unrealized gain (loss) on marketable securities, net of income tax benefit		(37)			(37)
Gain (loss) on derivative securities, effective portion, net of income tax expense		144			144
Foreign currency translation adjustment, including income tax expense (benefit)		(117)			(117)
Stock-based compensation expense		479	$ 479	0
Common stock issued under equity compensation plan, shares			67
Common stock issued under equity compensation plan, net of shares withheld for tax payments		(99)	$ (99)
Repurchased shares, in shares			(211)
Repurchased shares		(2,718)	$ (150)	(2,568)
Balance, shares at Mar. 31, 2018			30,161
Ending balance at Mar. 31, 2018		184,900	$ 230	184,939	(269)
Beginning balance at Dec. 31, 2017		179,189	$ 0	179,448	(259)
Balance, shares at Dec. 31, 2017			30,305
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	[1]	8,987
Unrealized gain (loss) on marketable securities, net of income tax benefit	[1]	(3)
Gain (loss) on derivative securities, effective portion, net of income tax expense	[1]	156
Foreign currency translation adjustment, including income tax expense (benefit)	[1]	(455)
Balance, shares at Jun. 30, 2018			30,237
Ending balance at Jun. 30, 2018		185,590	$ 462	185,689	(561)
Beginning balance at Mar. 31, 2018		184,900	$ 230	184,939	(269)
Balance, shares at Mar. 31, 2018			30,161
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income		928		928
Unrealized gain (loss) on marketable securities, net of income tax benefit		34			34
Gain (loss) on derivative securities, effective portion, net of income tax expense		12			12
Foreign currency translation adjustment, including income tax expense (benefit)		(338)			(338)
Stock-based compensation expense		268	$ 268	0
Common stock issued under equity compensation plan, shares			87
Common stock issued under equity compensation plan, net of shares withheld for tax payments		(198)	$ (198)
Common stock issued under employee stock purchase plan, shares			20
Common stock issued under employee stock purchase plan		232	$ 232
Repurchased shares, in shares			(31)
Repurchased shares		(248)	$ (70)	(178)
Balance, shares at Jun. 30, 2018			30,237
Ending balance at Jun. 30, 2018		185,590	$ 462	185,689	(561)
Beginning balance at Dec. 31, 2018		182,596	$ 215	183,290	(909)
Balance, shares at Dec. 31, 2018			29,545
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income		(8,575)		(8,575)
Unrealized gain (loss) on marketable securities, net of income tax benefit		15			15
Gain (loss) on derivative securities, effective portion, net of income tax expense		(100)			(100)
Foreign currency translation adjustment, including income tax expense (benefit)		128			128
Stock-based compensation expense		(365)	$ (147)	(218)
Common stock issued under equity compensation plan, shares			48
Common stock issued under equity compensation plan, net of shares withheld for tax payments		(68)	$ (68)
Balance, shares at Mar. 31, 2019			29,593
Ending balance at Mar. 31, 2019		173,631	$ 0	174,497	(866)
Beginning balance at Dec. 31, 2018		182,596	$ 215	183,290	(909)
Balance, shares at Dec. 31, 2018			29,545
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income		(87,443)
Unrealized gain (loss) on marketable securities, net of income tax benefit		6
Gain (loss) on derivative securities, effective portion, net of income tax expense		(223)
Foreign currency translation adjustment, including income tax expense (benefit)		200
Balance, shares at Jun. 30, 2019			29,728
Ending balance at Jun. 30, 2019		94,916	$ 213	95,629	(926)
Beginning balance at Mar. 31, 2019		173,631	$ 0	174,497	(866)
Balance, shares at Mar. 31, 2019			29,593
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income		(78,868)		(78,868)
Unrealized gain (loss) on marketable securities, net of income tax benefit		(9)			(9)
Gain (loss) on derivative securities, effective portion, net of income tax expense		(123)			(123)
Foreign currency translation adjustment, including income tax expense (benefit)		72			72
Stock-based compensation expense		9	$ 9	0
Common stock issued under equity compensation plan, shares			87
Common stock issued under equity compensation plan, net of shares withheld for tax payments		36	$ 36
Common stock issued under employee stock purchase plan, shares			48
Common stock issued under employee stock purchase plan		168	$ 168
Balance, shares at Jun. 30, 2019			29,728
Ending balance at Jun. 30, 2019		$ 94,916	$ 213	$ 95,629	$ (926)

[1]