STATEMENT OF STOCKHOLDERS' EQUITY Statement - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income	Retained Earnings
Beginning balance at Dec. 31, 2017		$ 29	$ 198,384	$ (2,139)	$ 351,408
Common stock issued under employee stock plans		0	4,657
Repurchase of common stock		0	(33,314)
Stock-based compensation expense			5,625
Other comprehensive income (loss)	$ (243)			(243)
Net income	14,200				14,200
Payment of dividends to stockholders					(4,775)
Ending balance at Mar. 31, 2018	533,832	29	175,352	(2,382)	360,833
Beginning balance at Dec. 31, 2018	527,072	28	126,164	(1,689)	402,569
Common stock issued under employee stock plans		0	4,500
Repurchase of common stock	(7,302)	0	(7,302)
Stock-based compensation expense			4,407
Other comprehensive income (loss)	328			328
Net income	7,233				7,233
Payment of dividends to stockholders					(4,937)
Ending balance at Mar. 31, 2019	$ 531,301	$ 28	$ 127,769	$ (1,361)	$ 404,865