Significant Accounting Policies, Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended		1 Months Ended	9 Months Ended	1 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Oct. 30, 2013 Stock Options [Member] Subsequent Event [Member]	Sep. 30, 2012 Options and Restricted Stock Units [Member]	Oct. 30, 2013 Restricted Stock Units (RSUs) [Member] Subsequent Event [Member]
Earnings (loss) per share:
Net income (loss)	$ 3,032	$ 291	$ 7,511	$ (6,722)
Basic [Abstract]
Weighted-average shares of common stock outstanding (in shares)	52,266,000	48,707,000	51,080,000	48,571,000
Shares used in computing basic earnings (loss) per share (in shares)	52,266,000	48,707,000	51,080,000	48,571,000
Basic earnings (loss) per share (in dollars per share)	$ 0.06	$ 0.01	$ 0.15	$ (0.14)
Diluted [Abstract]
Weighted-average shares of common stock outstanding (in shares)	52,266,000	48,707,000	51,080,000	48,571,000
Add: Common equivalent shares outstanding (in shares)	2,395,000	1,619,000	2,428,000	0
Shares used in computing diluted earnings (loss) per share (in shares)	54,661,000	50,326,000	53,508,000	48,571,000
Diluted earnings (loss) per share (in dollars per share)	$ 0.06	$ 0.01	$ 0.14	$ (0.14)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from the computation of diluted earnings (loss) per share (in shares)					195,000	1,100,000	284,375
Weighted average stock options excluded from computation of diluted earnings (loss) per share (in shares)	999,000	2,900,000	1,200,000	2,900,000