Quarterly Financial Data (Unaudited) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended														12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Data (Unaudited) [Abstract]
Revenues	$ 38,878	$ 35,611	[1]	$ 38,977	[1]	$ 50,075	$ 63,490	$ 45,893	$ 58,065	$ 57,216	$ 54,791	$ 56,681	$ 58,906	$ 50,273	$ 163,541	$ 224,664	$ 220,651
Gross profit	28,088	26,896	[1]	30,208	[1]	39,730	50,777	36,827	46,675	45,350	43,019	45,400	46,551	39,039	124,922	179,629	174,009
Net income (loss)	$ (98,726)	$ (14,943)	[1]	$ (7,480)	[1]	$ (345)	$ 3,185	$ 886	$ 7,094	$ 7,212	$ 5,894	$ 7,525	$ 4,213	$ 4,857	$ (121,496)	$ 18,377	$ 22,489
Net income (loss) per share [Abstract]
Basic (in dollars per share)	$ (5.20)	$ (0.80)	[1]	$ (0.40)	[1]	$ (0.02)	$ 0.16	$ 0.04	$ 0.34	$ 0.35	$ 0.28	$ 0.35	$ 0.20	$ 0.26	$ (6.41)	$ 0.90	$ 1.10
Diluted (in dollars per share)	$ (5.20)	$ (0.80)	[1]	$ (0.40)	[1]	$ (0.02)	$ 0.16	$ 0.04	$ 0.34	$ 0.34	$ 0.27	$ 0.35	$ 0.20	$ 0.26	$ (6.41)	$ 0.89	$ 1.08
Shares used in computing net income (loss) per share [Abstract]
Basic (in shares)	19,041,451	18,724,419	[1]	18,723,484	[1]	18,719,419	19,400,341	19,982,967	20,573,048	20,678,023	20,947,985	21,205,675	20,547,244	18,339,977	18,940,355	20,454,970	20,355,520
Diluted (in shares)	19,041,451	18,724,419	[1]	18,723,484	[1]	18,719,419	19,602,611	20,441,262	21,033,349	21,147,583	21,356,819	21,752,845	21,034,814	18,876,163	18,940,355	20,657,240	20,764,354

[1] The information has been retroactively adjusted to account for the LCA business which is classified as held for sale as of December 31, 2014, as a discontinued operations.