Consolidated Statements of Stockholders' Equity Statement - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional paid-in capital	Accumulated other comprehensive (loss) income	Retained earnings
Balance (in shares) at Dec. 31, 2018		39,386
Balance at Dec. 31, 2018	$ 425,584	$ 39	$ 363,921	$ (139)	$ 61,763
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under equity compensation plans (in shares)		444
Issuance of common stock under equity compensation plans	8,817	$ 1	8,816
Stock-based compensation expense	2,887		2,887
Repurchases of common stock (in shares)		(24)
Repurchases of common stock	(1,476)		(1,476)
Other comprehensive gain, net of tax	(248)
Other comprehensive gain, net of tax				42
Net income	24,844				24,844
Balance (in shares) at Mar. 31, 2019		39,806
Balance at Mar. 31, 2019	460,698	$ 40	374,148	(97)	86,607
Balance (in shares) at Dec. 31, 2019		41,868
Balance at Dec. 31, 2019	559,820	$ 42	425,557	(463)	134,684
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under equity compensation plans (in shares)		153
Issuance of common stock under equity compensation plans	3,571	$ 0	3,571
Stock-based compensation expense	3,325		3,325
Repurchases of common stock (in shares)		(25)
Repurchases of common stock	(1,954)		(1,954)
Other comprehensive gain, net of tax	(65)
Other comprehensive gain, net of tax				200
Net income	40,237				40,237
Balance (in shares) at Mar. 31, 2020		41,996
Balance at Mar. 31, 2020	$ 605,199	$ 42	$ 430,499	$ (263)	$ 174,921