CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Common Stock	Retained Earnings Reclassify upon adoption of ASU	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Reclassify upon adoption of ASU	Total
Beginning balance (ASU 2016-13) at Dec. 31, 2019		$ (575)			$ (575)
Beginning balance at Dec. 31, 2019	$ 587,017		$ 368,221	$ (5,294)		$ 949,944
Beginning balance (in shares) at Dec. 31, 2019	55,213
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)			(3,154)			(3,154)
Other comprehensive income (loss)				(9,465)		(9,465)
Stock-based compensation expense	$ 2,641					2,641
Options exercised	$ 2,369					2,369
Options exercised (in shares)	174
Issuance of common stock under Employee Stock Purchase Plan	$ 371					371
Issuance of common stock under Employee Stock Purchase Plans (in shares)	13
Shares surrendered in exchange for payment of payroll tax liabilities	$ (866)					(866)
Shares surrendered in exchange for payment of payroll tax liabilities (in shares)	(23)
Shares surrendered in exchange for exercise of stock options	$ (1,467)					(1,467)
Shares surrendered in exchange for exercise of stock options (in shares)	(39)
Ending balance at Mar. 31, 2020	$ 590,065		364,492	(14,759)		939,798
Ending balance (in shares) at Mar. 31, 2020	55,338
Beginning balance (ASU 2016-13) at Dec. 31, 2019		$ (575)			$ (575)
Beginning balance at Dec. 31, 2019	$ 587,017		368,221	(5,294)		949,944
Beginning balance (in shares) at Dec. 31, 2019	55,213
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)						(25,221)
Other comprehensive income (loss)						(4,031)
Shares surrendered in exchange for exercise of stock options						(1,467)
Ending balance at Sep. 30, 2020	$ 600,737		342,425	(9,325)		933,837
Ending balance (in shares) at Sep. 30, 2020	55,538
Beginning balance at Mar. 31, 2020	$ 590,065		364,492	(14,759)		939,798
Beginning balance (in shares) at Mar. 31, 2020	55,338
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)			(19,058)			(19,058)
Other comprehensive income (loss)				2,446		2,446
Stock-based compensation expense	$ 3,197					3,197
Options exercised	$ 2,229					2,229
Options exercised (in shares)	138
Issuance of common stock under Employee Stock Purchase Plan	$ 235					235
Issuance of common stock under Employee Stock Purchase Plans (in shares)	5
Ending balance at Jun. 30, 2020	$ 595,726		345,434	(12,313)		928,847
Ending balance (in shares) at Jun. 30, 2020	55,481
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)			(3,009)			(3,009)
Other comprehensive income (loss)				2,988		2,988
Stock-based compensation expense	$ 3,794					3,794
Options exercised	$ 950					950
Options exercised (in shares)	50
Issuance of common stock under Employee Stock Purchase Plan	$ 267					267
Issuance of common stock under Employee Stock Purchase Plans (in shares)	7
Ending balance at Sep. 30, 2020	$ 600,737		342,425	(9,325)		933,837
Ending balance (in shares) at Sep. 30, 2020	55,538
Beginning balance at Dec. 31, 2020	$ 606,224		357,803	(5,452)		$ 958,575
Beginning balance (in shares) at Dec. 31, 2020	55,623					55,623
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)			10,958			$ 10,958
Other comprehensive income (loss)				(1,730)		(1,730)
Stock-based compensation expense	$ 3,310					3,310
Options exercised	$ 5,897					5,897
Options exercised (in shares)	291
Issuance of common stock under Employee Stock Purchase Plan	$ 263					263
Issuance of common stock under Employee Stock Purchase Plans (in shares)	5
Shares issued from time-vested restricted stock units (in shares)	25
Shares surrendered in exchange for payment of payroll tax liabilities	$ (488)					(488)
Shares surrendered in exchange for payment of payroll tax liabilities (in shares)	(9)
Shares surrendered in exchange for exercise of stock options	$ (93)					(93)
Shares surrendered in exchange for exercise of stock options (in shares)	(2)
Ending balance at Mar. 31, 2021	$ 615,113		368,761	(7,182)		976,692
Ending balance (in shares) at Mar. 31, 2021	55,933
Beginning balance at Dec. 31, 2020	$ 606,224		357,803	(5,452)		$ 958,575
Beginning balance (in shares) at Dec. 31, 2020	55,623					55,623
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)						$ 27,841
Other comprehensive income (loss)						(764)
Shares surrendered in exchange for exercise of stock options						(179)
Ending balance at Sep. 30, 2021	$ 633,948		385,644	(6,216)		$ 1,013,376
Ending balance (in shares) at Sep. 30, 2021	56,452					56,452
Beginning balance at Mar. 31, 2021	$ 615,113		368,761	(7,182)		$ 976,692
Beginning balance (in shares) at Mar. 31, 2021	55,933
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)			4,916			4,916
Other comprehensive income (loss)				2,348		2,348
Stock-based compensation expense	$ 2,765					2,765
Options exercised	$ 5,455					5,455
Options exercised (in shares)	253
Issuance of common stock under Employee Stock Purchase Plan	$ 258					258
Issuance of common stock under Employee Stock Purchase Plans (in shares)	4
Shares issued from time-vested restricted stock units (in shares)	34
Ending balance at Jun. 30, 2021	$ 623,591		373,677	(4,834)		992,434
Ending balance (in shares) at Jun. 30, 2021	56,224
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)			11,967			11,967
Other comprehensive income (loss)				(1,382)		(1,382)
Stock-based compensation expense	$ 4,411					4,411
Options exercised	$ 5,806					5,806
Options exercised (in shares)	225
Issuance of common stock under Employee Stock Purchase Plan	$ 314					314
Issuance of common stock under Employee Stock Purchase Plans (in shares)	5
Shares surrendered in exchange for payment of payroll tax liabilities	$ (88)					(88)
Shares surrendered in exchange for payment of payroll tax liabilities (in shares)	(1)
Shares surrendered in exchange for exercise of stock options	$ (86)					(86)
Shares surrendered in exchange for exercise of stock options (in shares)	(1)
Ending balance at Sep. 30, 2021	$ 633,948		$ 385,644	$ (6,216)		$ 1,013,376
Ending balance (in shares) at Sep. 30, 2021	56,452					56,452