Earnings Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Numerator:
Net (loss) income	$ 3,173	$ 3,803	$ (4,105)	$ 10,203
Denominator for basic (loss) earnings per share:
Weighted average common shares outstanding	23,019	22,840	22,982	22,816
Effect of dilutive securities:
Outstanding common stock equivalents	880	380		446
Denominator for diluted earnings per share	23,899	23,220	22,982	23,262
Basic (loss) earnings per share	$ 0.14	$ 0.17	$ (0.18)	$ 0.45
Diluted (loss) earnings per share	$ 0.13	$ 0.16	$ (0.18)	$ 0.44
Excluded outstanding share-based awards having an anti-dilutive effect	222	62	222	20