Net Income (Loss) Per Share - (Basic and Diluted Net Income Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Earnings Per Share [Abstract]
Net income (loss)	$ (378)	$ 6,318
Weighted-average shares outstanding — basic (in shares)	35,740	36,024
Dilutive effect of employee stock plans (in shares)	0	890
Weighted-average shares outstanding — diluted (in shares)	35,740	36,914
Net income per share — basic (in dollars per share)	$ (0.01)	$ 0.18
Net income per share — diluted (in dollars per share)	$ (0.01)	$ 0.17
Anti-dilutive weighted-average shares related to stock award plans (in shares)	2,045	484