Net Income Per Share (Computation Of Basic And Diluted Net Income Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Numerator for basic net income (loss) per share:
Net income	$ (120)	$ 3,518	$ 5,676	$ 9,157
Denominator for basic net income (loss) per share:
Weighted-average common shares outstanding (in shares)	36,361	35,761	36,139	35,659
Basic net income per share (in dollars per share)	$ 0.00	$ 0.10	$ 0.16	$ 0.26
Denominator for diluted net income (loss) per share:
Diluted weighted-average common shares outstanding (in shares)	36,361	36,596	36,862	36,634
Diluted net income per share (in dollars per share)	$ 0.00	$ 0.10	$ 0.15	$ 0.25
Common Stock
Denominator for basic net income (loss) per share:
Weighted-average common shares outstanding (in shares)	36,361	35,761	36,139	35,659
Stock Options And Restricted Stock Units
Denominator for diluted net income (loss) per share:
Dilutive stock options and restricted stock units (in shares)	0	835	674	975
Performance-Based Restricted Stock Units
Denominator for diluted net income (loss) per share:
Dilutive stock options and restricted stock units (in shares)	0	0	49	0