Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share [Abstract]
Net income	$ 603	$ 30,760	$ 30,518
Weighted-average shares outstanding — basic	36,156	35,857	35,650
Add: Dilutive effect of employee stock plans	708	861	972
Weighted-average shares outstanding — diluted	36,864	36,718	36,622
Net income, basic (usd per share)	$ 0.02	$ 0.86	$ 0.86
Net income, diluted (usd per share)	$ 0.02	$ 0.84	$ 0.83
Anti-dilutive weighted-average shares related to stock award plans	1,345	555	640