Equity Method Investments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			3 Months Ended					3 Months Ended		12 Months Ended		1 Months Ended	3 Months Ended		3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Mar. 31, 2013 WesPac	Mar. 31, 2012 WesPac	Dec. 31, 2012 WesPac	Jul. 01, 2010 WesPac	Jul. 01, 2010 WesPac Kealine	Mar. 31, 2013 Bernard	Mar. 31, 2012 Bernard	Dec. 31, 2012 Bernard	Dec. 31, 2009 Bernard	Dec. 31, 2012 Alvah, Inc.	Mar. 31, 2013 Alvah, Inc.	Nov. 17, 2012 Alvah, Inc.	Mar. 31, 2013 Alvah, Inc. ARB	Mar. 31, 2012 Alvah, Inc. ARB	Mar. 31, 2013 Alvah, Inc. Q3C	Mar. 31, 2012 Alvah, Inc. Q3C
Equity method investments
Membership interest (as a percent)							50.00%	50.00%				30.00%			49.00%
Balance sheet data
Assets				$ 16,397		$ 16,896			$ 592		$ 592		$ 2,177	$ 2,880
Liabilities				756		1,063			86		86		1,208	1,166
Net assets				15,641		15,833			506		506		969	1,714
Company's equity investment	13,082		12,813	11,367		11,463			150		150		1,200	1,565
Earnings data:
Revenue				39	400						3,435			2,716
Expenses				231	216						72			1,971
Earnings before taxes				(192)	184						3,363			745
Company's equity in earnings	269	1,101		(96)	92						1,009			365
Cost of investment												300
Amount distributed									0	4,200			200
Share in distribution		1,260							0	1,260			98
Subcontractor payments made to equity method investee																$ 1,486	$ 212	$ 1,245	$ 118