Supplementary Financial Data Supplementary Financial Data (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	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, 2013	Dec. 31, 2012	Dec. 31, 2011
Supplementary Financial Data [Abstract]
Revenue	$ 336,307	$ 275,195	$ 234,553	$ 190,727	$ 250,911	$ 208,875	$ 170,994	$ 131,125	$ 1,036,782	$ 761,905	$ 566,424
Gross margin	67,030	54,909	46,216	38,314	47,638	43,114	33,411	23,700
Net income (loss)	$ 13,043	$ 124,092	$ 6,045	$ 2,397	$ 5,015	$ 8,314	$ 3,204	$ (3,186)	$ 151,423	$ 13,347	$ (33,877)
Earnings Per Share, Basic	$ 0.54	$ 5.09	$ 0.25	$ 0.11	$ 0.23	$ 0.43	$ 0.17	$ (0.17)	$ 6.11	$ 0.68	$ (1.81)
Earnings Per Share, Diluted	$ 0.48	$ 4.22	$ 0.25	$ 0.11	$ 0.23	$ 0.42	$ 0.17	$ (0.17)	$ 5.24	$ 0.67	$ (1.81)
Basic Weighted Average Shares Outstanding	24,358	24,358	24,271	22,273	21,545	19,434	18,833	18,772	23,822	19,651	18,698
Diluted Weighted Average Shares Outstanding	29,783	29,745	24,646	22,688	21,961	20,273	19,031	18,772	28,763	19,891	18,698