Business Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Segment Reporting Information [Line Items]
Revenue from reportable segments	$ 587,849	$ 592,118	$ 975,192	$ 907,664
Elimination of intersegment revenue	(37,687)	(52,503)	(46,326)	(57,889)
Revenue from external customers	550,162	539,615	928,866	849,775
Gross profit	51,197	51,916	81,253	76,852
Depreciation, Depletion and Amortization, Nonproduction	15,106	11,321	28,306	23,547
Assets	1,701,404	1,507,647	1,701,404	1,507,647	1,729,487
Reconciliation from Segment Totals to Consolidated [Abstract]
Gross profit	51,197	51,916	81,253	76,852
Selling, general and administrative expenses	46,454	40,806	104,112	85,882
Gain on restructuring	0	0	(497)	(1,888)
Gain on sales of property and equipment	3,306	2,954	4,394	4,871
Other income (expense), net	(3,117)	(7,718)	(5,954)	(3,602)
Income (loss) before benefit from income taxes	4,932	6,346	(23,922)	(5,873)
Construction [Member]
Segment Reporting Information [Line Items]
Revenue from reportable segments	308,602	245,113	485,720	363,059
Elimination of intersegment revenue	0	0	0	0
Revenue from external customers	308,602	245,113	485,720	363,059
Gross profit	25,154	17,961	38,353	26,541
Depreciation, Depletion and Amortization, Nonproduction	6,033	3,233	11,692	6,813
Assets	161,524	110,119	161,524	110,119
Reconciliation from Segment Totals to Consolidated [Abstract]
Gross profit	25,154	17,961	38,353	26,541
Large Project Construction [Member]
Segment Reporting Information [Line Items]
Revenue from reportable segments	181,371	228,799	353,086	392,727
Elimination of intersegment revenue	0	0	0	0
Revenue from external customers	181,371	228,799	353,086	392,727
Gross profit	22,088	28,239	44,808	50,488
Depreciation, Depletion and Amortization, Nonproduction	3,182	909	5,158	2,177
Assets	206,778	119,652	206,778	119,652
Reconciliation from Segment Totals to Consolidated [Abstract]
Gross profit	22,088	28,239	44,808	50,488
Construction Materials [Member]
Segment Reporting Information [Line Items]
Revenue from reportable segments	97,872	115,852	136,261	146,861
Elimination of intersegment revenue	(37,687)	(52,503)	(46,326)	(57,889)
Revenue from external customers	60,185	63,349	89,935	88,972
Gross profit	3,954	5,000	(2,020)	(950)
Depreciation, Depletion and Amortization, Nonproduction	5,891	7,179	11,456	14,557
Assets	351,295	365,690	351,295	365,690
Reconciliation from Segment Totals to Consolidated [Abstract]
Gross profit	3,954	5,000	(2,020)	(950)
Real Estate Segment [Member]
Segment Reporting Information [Line Items]
Revenue from reportable segments	4	2,354	125	5,017
Elimination of intersegment revenue	0	0	0	0
Revenue from external customers	4	2,354	125	5,017
Gross profit	1	716	112	773
Depreciation, Depletion and Amortization, Nonproduction	0	0	0	0
Assets	50,697	57,367	50,697	57,367
Reconciliation from Segment Totals to Consolidated [Abstract]
Gross profit	1	716	112	773
Operating Segments [Member]
Segment Reporting Information [Line Items]
Assets	$ 770,294	$ 652,828	$ 770,294	$ 652,828