Business Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Segment Reporting Information [Line Items]
Total revenue from reportable segments									$ 2,262,428	$ 2,204,566	$ 1,960,262
Elimination of intersegment revenue									(179,391)	(195,035)	(197,297)
Revenue from external customers	504,781	728,482	539,615	310,160	539,548	728,578	484,674	256,731	2,083,037	2,009,531	1,762,965
Gross profit	56,808	101,099	51,916	24,936	79,126	93,893	44,956	29,988	234,759	247,963	177,784
Depreciation, depletion and amortization									46,242	48,155	54,994
Segment assets	1,729,487				1,547,799				1,729,487	1,547,799	1,535,533
Reconciliation from Segment Totals to Consolidated [Abstract]
Gross profit (loss)	56,808	101,099	51,916	24,936	79,126	93,893	44,956	29,988	234,759	247,963	177,784
Selling, general and administrative expenses									185,099	162,302	191,593
Restructuring (gain) charges									(3,728)	2,181	109,279
Gain on sales of property and equipment	18,000								27,447	15,789	13,748
Other (expense) income, net									194	(9,836)	2,964
Income (loss) before provision for (benefit from) income taxes									81,029	89,433	(106,376)
Cash and cash equivalents	321,990				256,990				321,990	256,990	252,022	338,956
Receivables, net	325,529				251,838				325,529	251,838
Deferred income taxes	36,687				38,571				36,687	38,571
Other current assets	31,834				35,171				31,834	35,171
Property and equipment, net	481,478				447,140				481,478	447,140
Other noncurrent assets	84,392				70,716				84,392	70,716
Reportable Segment [Member]
Segment Reporting Information [Line Items]
Segment assets	734,521				649,890				734,521	649,890	665,303
Construction [Member]
Segment Reporting Information [Line Items]
Total revenue from reportable segments									984,106	1,043,614	943,245
Elimination of intersegment revenue									0	0	0
Revenue from external customers									984,106	1,043,614	943,245
Gross profit									77,963	124,506	95,709
Depreciation, depletion and amortization									13,225	14,747	18,148
Segment assets	163,287				111,780				163,287	111,780	123,153
Reconciliation from Segment Totals to Consolidated [Abstract]
Gross profit (loss)									77,963	124,506	95,709
Large Project Construction [Member]
Segment Reporting Information [Line Items]
Total revenue from reportable segments									863,217	725,043	584,406
Elimination of intersegment revenue									0	0	0
Revenue from external customers									863,217	725,043	584,406
Gross profit									148,418	104,108	67,307
Depreciation, depletion and amortization									4,527	4,547	2,759
Segment assets	173,142				110,441				173,142	110,441	80,259
Reconciliation from Segment Totals to Consolidated [Abstract]
Gross profit (loss)									148,418	104,108	67,307
Construction Materials [Member]
Segment Reporting Information [Line Items]
Total revenue from reportable segments									410,033	415,618	419,355
Elimination of intersegment revenue									(179,391)	(195,035)	(197,297)
Revenue from external customers									230,642	220,583	222,058
Gross profit									7,572	16,641	12,018
Depreciation, depletion and amortization									28,490	28,672	33,565
Segment assets	347,869				352,619				347,869	352,619	374,205
Reconciliation from Segment Totals to Consolidated [Abstract]
Gross profit (loss)									7,572	16,641	12,018
Real Estate Segment [Member]
Segment Reporting Information [Line Items]
Total revenue from reportable segments									5,072	20,291	13,256
Elimination of intersegment revenue									0	0	0
Revenue from external customers									5,072	20,291	13,256
Gross profit									806	2,708	2,750
Depreciation, depletion and amortization									0	189	522
Segment assets	50,223				75,050				50,223	75,050	87,686
Reconciliation from Segment Totals to Consolidated [Abstract]
Gross profit (loss)									806	2,708	2,750
Unallocated Amount to Segment [Member]
Reconciliation from Segment Totals to Consolidated [Abstract]
Cash and cash equivalents	321,990				256,990				321,990	256,990	252,022
Short-term and long-term marketable securities	111,430				149,658				111,430	149,658	143,706
Receivables, net	325,529				251,838				325,529	251,838	243,986
Deferred income taxes	36,687				38,571				36,687	38,571	53,877
Other current assets	67,726				76,074				67,726	76,074	55,970
Property and equipment, net	50,857				46,180				50,857	46,180	42,874
Other noncurrent assets	$ 80,747				$ 78,598				$ 80,747	$ 78,598	$ 77,795