Description of Business and Summary of Significant Accounting Policies (Computation of basic and diluted net income (loss) per share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended																12 Months Ended
	Dec. 31, 2015	[1]	Sep. 30, 2015	[2]	Jun. 30, 2015	[3]	Mar. 31, 2015	[4]	Dec. 31, 2014	[5]	Sep. 30, 2014	[6]	Jun. 30, 2014	[7]	Mar. 31, 2014	[8]	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of computation of basic and diluted net income (loss) per share
Net income (loss)	$ (2,167)		$ (1,449)		$ (9,376)		$ (9,341)		$ (2,118)		$ (3,292)		$ (1,181)		$ 319		$ (22,333)	$ (6,272)	$ 6,340
Weighted average common shares outstanding																	30,716	29,216	28,869
Effect of potentially dilutive securities
Weighted average common shares outstanding, assuming dilution																	30,716	29,216	28,903
Net income (loss) per share:
Basic (in dollars per share)																	$ (0.73)	$ (0.21)	$ 0.22
Diluted (in dollars per share)																	$ (0.73)	$ (0.21)	$ 0.22
Options to purchase common stock
Effect of potentially dilutive securities
Effect of potentially dilutive securities																	0	0	16
Restricted Stock Awards
Effect of potentially dilutive securities
Effect of potentially dilutive securities																	0	0	3
Restricted Stock Units
Effect of potentially dilutive securities
Effect of potentially dilutive securities																	0	0	14
Employee Stock Purchase Plan
Effect of potentially dilutive securities
Effect of potentially dilutive securities																	0	0	1

[1] Includes a non-cash expense for stock-based compensation of $1.0 million.

[2] Includes a non-cash expense for stock-based compensation of $1.1 million.

[3] Includes restructuring costs of $2.3 million, a non-cash deferred tax expense of $2.1 million in connection with the probable repatriation of a portion of the unremitted earnings of a foreign subsidiary and a non-cash expense for stock-based compensation of $1.0 million.

[4] Includes a non-cash expense for stock-based compensation of $839,000.

[5] Includes non-cash deferred tax expense of $1.6 million in connection with the probable repatriation of a portion of the unremitted earnings of a foreign subsidiary and a non-cash expense for stock-based compensation of $1.0 million.

[6] Includes a non-cash expense for stock-based compensation of $1.0 million.

[7] Includes a non-cash expense for stock-based compensation of $1.2 million

[8] Includes a non-cash expense for stock-based compensation of $755,000.