Basis of Presentation - Schedule of Reclassifications (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Total revenue	$ 719,764	$ 739,752	$ 1,685,481	$ 1,668,803
Gross Profit	66,692	55,860	170,515	135,513
Selling, general and administrative expenses	47,386	45,527	147,731	149,477
Gain (Loss) on Disposition of Property Plant Equipment			6,891	7,653
Stock-based compensation			8,933	10,645
Operating Income (Loss)	22,310	13,592	29,675	(6,311)
Income (loss) before provision for (benefit from) income taxes	20,186	11,478	23,352	(14,379)
Provision for (benefit from) income taxes	6,081	4,946	8,301	(2,867)
Net income (loss) attributable to Granite Construction Incorporated	15,282	13,037	8,370	(7,526)
Basic (in dollars per share)	$ 0.39	$ 0.34	$ 0.21	$ (0.19)
Diluted (in dollars per share)	$ 0.38	$ 0.33	$ 0.21	$ (0.19)
Total current assets	1,020,829	1,041,304	1,020,829	1,041,304	950,203
Total assets	1,683,043	1,727,134	1,683,043	1,727,134	1,617,155
Total current liabilities	544,167	565,961	544,167	565,961	497,570
Total Granite Construction Incorporated shareholders’ equity	780,804	813,250	780,804	813,250	781,940
Non-controlling interests	26,259	16,265	26,259	16,265	4,404
Total liabilities and equity	1,683,043	1,727,134	1,683,043	1,727,134	1,617,155
Net income (loss)	14,105	6,532	15,051	(11,512)
Depreciation, depletion and amortization			49,968	54,788
Equity in net income from unconsolidated joint ventures			(27,001)	(51,826)
Increase (Decrease) in Accounts and Other Receivables			103,913	99,856
Costs and estimated earnings in excess of billings, net			44,126	16,064
Increase (Decrease) in Inventories			12,131	1,882
Contributions to unconsolidated construction joint ventures			24,797	28,514
Distributions from unconsolidated construction joint ventures			46,991	68,033
Other assets, net			(7,250)	4,820
Accrued expenses and other current liabilities, net			123	20,942
Non-cash Activity, Increase (Decrease) in Performance Guarantees			21,332	24,202
Accounts payable			43,710	3,204
As Reported
Total revenue		741,575		1,670,441
Cost of Revenue		687,179		1,534,791
Gross Profit		54,396		135,650
Selling, general and administrative expenses		47,060		150,675
Gain (Loss) on Disposition of Property Plant Equipment		3,259		(7,653)
Stock-based compensation				10,645
Operating Income (Loss)		10,595		(7,372)
Income (loss) before provision for (benefit from) income taxes		8,481		(15,440)
Provision for (benefit from) income taxes		4,026		(3,235)
Income (Loss) Attributable to Noncontrolling Interest		6,542		3,938
Net income (loss) attributable to Granite Construction Incorporated		10,997		(8,267)
Basic (in dollars per share)		$ 0.28		$ (0.21)
Diluted (in dollars per share)		$ 0.28		$ (0.21)
Total current assets		1,041,672		1,041,672
Noncurrent assets		684,330		684,330
Total assets		1,726,002		1,726,002
Total current liabilities		565,522		565,522
Noncurrent liabilities		331,658		331,658
Total Granite Construction Incorporated shareholders’ equity		812,509		812,509
Non-controlling interests		16,313		16,313
Total liabilities and equity		1,726,002		1,726,002
Net income (loss)		4,455		(12,205)
Depreciation, depletion and amortization				54,788
Restructuring Costs and Asset Impairment Charges				(23)
Equity in net income from unconsolidated joint ventures				0
Increase (Decrease) in Accounts and Other Receivables				(99,856)
Costs and estimated earnings in excess of billings, net				(1,707)
Increase (Decrease) in Inventories				(1,882)
Equity in construction joint ventures				(54,672)
Contributions to unconsolidated construction joint ventures				0
Distributions from unconsolidated construction joint ventures				0
Other assets, net				(5,165)
Increase (Decrease) in Accounts Payable				5,578
Accrued expenses and other current liabilities, net				47,637
Total				(64,515)
Reclassifications
Total revenue		(1,823)		(1,638)
Cost of Revenue		(3,287)		(1,501)
Gross Profit		1,464		(137)
Selling, general and administrative expenses		(1,533)		(1,198)
Gain (Loss) on Disposition of Property Plant Equipment		0		0
Stock-based compensation				0
Operating Income (Loss)		2,997		1,061
Income (loss) before provision for (benefit from) income taxes		2,997		1,061
Provision for (benefit from) income taxes		920		368
Income (Loss) Attributable to Noncontrolling Interest		(37)		48
Net income (loss) attributable to Granite Construction Incorporated		2,040		741
Basic (in dollars per share)		$ 0.06		$ 0.02
Diluted (in dollars per share)		$ 0.05		$ 0.02
Total current assets		(368)		(368)
Noncurrent assets		1,500		1,500
Total assets		1,132		1,132
Total current liabilities		439		439
Noncurrent liabilities		0		0
Total Granite Construction Incorporated shareholders’ equity		741		741
Non-controlling interests		(48)		(48)
Total liabilities and equity		1,132		1,132
Net income (loss)		2,077		693
Depreciation, depletion and amortization				0
Restructuring Costs and Asset Impairment Charges				0
Equity in net income from unconsolidated joint ventures				0
Increase (Decrease) in Accounts and Other Receivables				0
Costs and estimated earnings in excess of billings, net				137
Increase (Decrease) in Inventories				0
Equity in construction joint ventures				0
Contributions to unconsolidated construction joint ventures				0
Distributions from unconsolidated construction joint ventures				0
Other assets, net				368
Increase (Decrease) in Accounts Payable				(1,198)
Accrued expenses and other current liabilities, net				0
Total				0
Adjusted
Total revenue		739,752		1,668,803
Cost of Revenue		683,892		1,533,290
Gross Profit		55,860		135,513
Selling, general and administrative expenses		45,527		149,477
Gain (Loss) on Disposition of Property Plant Equipment		3,259		(7,653)
Stock-based compensation				10,645
Operating Income (Loss)		13,592		(6,311)
Income (loss) before provision for (benefit from) income taxes		11,478		(14,379)
Provision for (benefit from) income taxes		4,946		(2,867)
Income (Loss) Attributable to Noncontrolling Interest		6,505		3,986
Net income (loss) attributable to Granite Construction Incorporated		13,037		(7,526)
Basic (in dollars per share)		$ 0.34		$ (0.19)
Diluted (in dollars per share)		$ 0.33		$ (0.19)
Total current assets		1,041,304		1,041,304
Noncurrent assets		685,830		685,830
Total assets		1,727,134		1,727,134
Total current liabilities		565,961		565,961
Noncurrent liabilities		331,658		331,658
Total Granite Construction Incorporated shareholders’ equity		813,250		813,250
Non-controlling interests		16,265		16,265
Total liabilities and equity		1,727,134		1,727,134
Net income (loss)		6,532		(11,512)
Depreciation, depletion and amortization				54,788
Restructuring Costs and Asset Impairment Charges				0
Equity in net income from unconsolidated joint ventures				(51,826)
Increase (Decrease) in Accounts and Other Receivables				(99,856)
Costs and estimated earnings in excess of billings, net				(16,064)
Increase (Decrease) in Inventories				(1,882)
Equity in construction joint ventures				0
Contributions to unconsolidated construction joint ventures				(28,514)
Distributions from unconsolidated construction joint ventures				68,033
Other assets, net				(4,820)
Increase (Decrease) in Accounts Payable				3,204
Accrued expenses and other current liabilities, net				20,942
Total				(64,515)
Adjustment for Error Correction, Reclassification [Member]
Gain (Loss) on Disposition of Property Plant Equipment				0
Stock-based compensation				0
Net income (loss)				0
Depreciation, depletion and amortization				0
Restructuring Costs and Asset Impairment Charges				23
Equity in net income from unconsolidated joint ventures				(51,826)
Increase (Decrease) in Accounts and Other Receivables				0
Costs and estimated earnings in excess of billings, net				(14,494)
Increase (Decrease) in Inventories				0
Equity in construction joint ventures				54,672
Contributions to unconsolidated construction joint ventures				(28,514)
Distributions from unconsolidated construction joint ventures				68,033
Other assets, net				(23)
Increase (Decrease) in Accounts Payable				(1,176)
Accrued expenses and other current liabilities, net				(26,695)
Total				$ 0