Intangible Assets - Finite Lived Intangible Assets (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Total amortized intangible assets, Gross Value	$ 48,570,000	$ 34,370,000	$ 48,570,000	$ 34,370,000	$ 49,370,000
Total amortized intangible assets, Accumulated Amortization	(19,784,000)	(13,744,000)	(19,784,000)	(13,744,000)	(15,319,000)
Total amortized intangible assets, Net Value	28,786,000	20,626,000	28,786,000	20,626,000	34,051,000
Amortization expense	2,300,000	1,000,000	4,500,000	2,100,000
Future amortization expense, Remainder of Fiscal Year	4,800,000		4,800,000
Future amortization expense, Year One	2,200,000		2,200,000
Future amortization expense, Year Two	2,100,000		2,100,000
Future amortization expense, Year Three	1,800,000		1,800,000
Future amortization expense, Year Four	1,800,000		1,800,000
Future amortization expense, after Year Four	16,100,000		16,100,000
Permits [Member]
Finite-Lived Intangible Assets [Line Items]
Total amortized intangible assets, Gross Value	29,713,000	29,713,000	29,713,000	29,713,000	29,713,000
Total amortized intangible assets, Accumulated Amortization	(11,430,000)	(9,494,000)	(11,430,000)	(9,494,000)	(10,869,000)
Total amortized intangible assets, Net Value	18,283,000	20,219,000	18,283,000	20,219,000	18,844,000
Customer Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Total amortized intangible assets, Gross Value	4,398,000	2,198,000	4,398,000	2,198,000	4,698,000
Total amortized intangible assets, Accumulated Amortization	(2,344,000)	(2,056,000)	(2,344,000)	(2,056,000)	(2,170,000)
Total amortized intangible assets, Net Value	2,054,000	142,000	2,054,000	142,000	2,528,000
Covenants not to compete [Member]
Finite-Lived Intangible Assets [Line Items]
Total amortized intangible assets, Gross Value	1,588,000	1,588,000	1,588,000	1,588,000	1,588,000
Total amortized intangible assets, Accumulated Amortization	(1,550,000)	(1,536,000)	(1,550,000)	(1,536,000)	(1,546,000)
Total amortized intangible assets, Net Value	38,000	52,000	38,000	52,000	42,000
Order or Production Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Total amortized intangible assets, Gross Value	7,900,000		7,900,000		7,900,000
Total amortized intangible assets, Accumulated Amortization	(3,447,000)		(3,447,000)		0
Total amortized intangible assets, Net Value	4,453,000		4,453,000		8,400,000
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Total amortized intangible assets, Gross Value	4,100,000		4,100,000		4,100,000
Total amortized intangible assets, Accumulated Amortization	(216,000)		(216,000)		0
Total amortized intangible assets, Net Value	3,884,000		3,884,000		4,100,000
Other [Member]
Finite-Lived Intangible Assets [Line Items]
Total amortized intangible assets, Gross Value	871,000	871,000	871,000	871,000	871,000
Total amortized intangible assets, Accumulated Amortization	(797,000)	(658,000)	(797,000)	(658,000)	(734,000)
Total amortized intangible assets, Net Value	74,000	213,000	74,000	213,000	137,000
Scenario, Previously Reported [Member] | Order or Production Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Total amortized intangible assets, Gross Value					$ 8,400,000