Basis of Presentation - Schedule of Reclassifications (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Total revenue	$ 585,870,000	$ 550,348,000	$ 965,717,000	$ 929,052,000
Gross Profit	82,415,000	49,596,000	103,822,000	79,652,000
Selling, general and administrative expenses	51,098,000	46,789,000	100,346,000	103,950,000
Operating Income (Loss)	34,310,000	6,113,000	7,362,000	(19,904,000)
Income (loss) before provision for (benefit from) income taxes	32,491,000	2,996,000	3,165,000	(25,858,000)
Provision for (benefit from) income taxes	10,284,000	1,214,000	2,220,000	(7,813,000)
Net income (loss) attributable to Granite Construction Incorporated	13,641,000	1,419,000	(6,913,000)	(20,563,000)
Basic (in dollars per share)	$ 0.35	$ 0.04	$ (0.18)	$ (0.53)
Diluted (in dollars per share)	$ 0.34	$ 0.04	$ (0.18)	$ (0.53)
Total current assets	977,920,000	1,009,166,000	977,920,000	1,009,166,000	950,203,000
Total assets	1,653,386,000	1,700,668,000	1,653,386,000	1,700,668,000	1,617,155,000
Total current liabilities	525,329,000	535,511,000	525,329,000	535,511,000	497,570,000
Total Granite Construction Incorporated shareholders’ equity	768,477,000	803,068,000	768,477,000	803,068,000	781,940,000
Non-controlling interests	25,066,000	29,715,000	25,066,000	29,715,000	4,404,000
Total liabilities and equity	1,653,386,000	1,700,668,000	1,653,386,000	1,700,668,000	1,617,155,000
Net income (loss)	22,207,000	1,782,000	945,000	(18,045,000)
Depreciation, depletion and amortization			31,878,000	34,362,000
Equity in net income from unconsolidated joint ventures			(25,724,000)	(31,201,000)
Costs and estimated earnings in excess of billings, net			(56,150,000)	(35,243,000)
Contributions to unconsolidated construction joint ventures			(13,797,000)	(16,209,000)
Distributions from unconsolidated construction joint ventures			16,528,000	42,486,000
Other assets, net			(1,579,000)	(6,519,000)
Accrued expenses and other current liabilities, net			(9,849,000)	5,531,000
Non-cash Activity, Increase (Decrease) in Performance Guarantees			617,000
Accounts payable			42,235,000	(11,724,000)
As Reported
Total revenue		550,162,000		928,866,000
Cost of Revenue		498,965,000		847,613,000
Gross Profit		51,197,000		81,253,000
Selling, general and administrative expenses		46,454,000		103,615,000
Operating Income (Loss)		8,049,000		(17,968,000)
Income (loss) before provision for (benefit from) income taxes		4,932,000		(23,922,000)
Provision for (benefit from) income taxes		1,766,000.00		(7,261,000)
Income (Loss) Attributable to Noncontrolling Interest		(448,000)		(2,603,000)
Net income (loss) attributable to Granite Construction Incorporated		2,718,000		(19,264,000)
Basic (in dollars per share)		$ 0.07		$ (0.50)
Diluted (in dollars per share)		$ 0.07		$ (0.50)
Total current assets		1,009,530,000		1,009,530,000
Noncurrent assets		691,874,000		691,874,000
Total assets		1,701,404,000		1,701,404,000
Total current liabilities		534,856,000		534,856,000
Noncurrent liabilities		332,374,000		332,374,000
Total Granite Construction Incorporated shareholders’ equity		804,367,000		804,367,000
Non-controlling interests		29,807,000		29,807,000
Total liabilities and equity		1,701,404,000		1,701,404,000
Net income (loss)		3,166,000.00		(16,661,000)
Depreciation, depletion and amortization				33,988,000
Equity in net income from unconsolidated joint ventures				0
Costs and estimated earnings in excess of billings, net				24,873,000
Equity in construction joint ventures				(42,336,000)
Contributions to unconsolidated construction joint ventures				0
Distributions from unconsolidated construction joint ventures				0
Other assets, net				5,957,000
Increase (Decrease) in Accounts Payable				(10,548,000)
Accrued expenses and other current liabilities, net				29,825,000
Total				(36,562,000)
Reclassifications
Total revenue		186,000		186,000
Cost of Revenue		1,787,000		1,787,000
Gross Profit		(1,601,000)		(1,601,000)
Selling, general and administrative expenses		335,000		335,000
Operating Income (Loss)		(1,936,000)		(1,936,000)
Income (loss) before provision for (benefit from) income taxes		(1,936,000)		(1,936,000)
Provision for (benefit from) income taxes		(552,000.00)		(552,000)
Income (Loss) Attributable to Noncontrolling Interest		85,000		85,000
Net income (loss) attributable to Granite Construction Incorporated		(1,299,000)		(1,299,000)
Basic (in dollars per share)		$ (0.03)		$ (0.03)
Diluted (in dollars per share)		$ (0.03)		$ (0.03)
Total current assets		(364,000)		(364,000)
Noncurrent assets		(372,000)		(372,000)
Total assets		(736,000)		(736,000)
Total current liabilities		655,000		655,000
Noncurrent liabilities		0		0
Total Granite Construction Incorporated shareholders’ equity		(1,299,000)		(1,299,000)
Non-controlling interests		(92,000)		(92,000)
Total liabilities and equity		(736,000)		(736,000)
Net income (loss)		(1,384,000.00)		(1,384,000)
Depreciation, depletion and amortization				374,000
Equity in net income from unconsolidated joint ventures				0
Costs and estimated earnings in excess of billings, net				(1,335,000)
Equity in construction joint ventures				0
Contributions to unconsolidated construction joint ventures				0
Distributions from unconsolidated construction joint ventures				0
Other assets, net				562,000
Increase (Decrease) in Accounts Payable				0
Accrued expenses and other current liabilities, net				237,000
Non-cash Activity, Increase (Decrease) in Performance Guarantees				(21,813,000)
Total				0
Adjusted
Total revenue		550,348,000		929,052,000
Cost of Revenue		500,752,000		849,400,000
Gross Profit		49,596,000		79,652,000
Selling, general and administrative expenses		46,789,000		103,950,000
Operating Income (Loss)		6,113,000		(19,904,000)
Income (loss) before provision for (benefit from) income taxes		2,996,000		(25,858,000)
Provision for (benefit from) income taxes		1,214,000.00		(7,813,000)
Income (Loss) Attributable to Noncontrolling Interest		(363,000)		(2,518,000)
Net income (loss) attributable to Granite Construction Incorporated		1,419,000		(20,563,000)
Basic (in dollars per share)		$ 0.04		$ (0.53)
Diluted (in dollars per share)		$ 0.04		$ (0.53)
Total current assets		1,009,166,000		1,009,166,000
Noncurrent assets		691,502,000		691,502,000
Total assets		1,700,668,000		1,700,668,000
Total current liabilities		535,511,000		535,511,000
Noncurrent liabilities		332,374,000		332,374,000
Total Granite Construction Incorporated shareholders’ equity		803,068,000		803,068,000
Non-controlling interests		29,715,000		29,715,000
Total liabilities and equity		1,700,668,000		1,700,668,000
Net income (loss)		1,782,000.00		(18,045,000)
Depreciation, depletion and amortization				34,362,000
Equity in net income from unconsolidated joint ventures				(31,201,000)
Costs and estimated earnings in excess of billings, net				35,243,000
Equity in construction joint ventures				0
Contributions to unconsolidated construction joint ventures				16,209,000
Distributions from unconsolidated construction joint ventures				42,486,000
Other assets, net				6,519,000
Increase (Decrease) in Accounts Payable				(11,724,000)
Accrued expenses and other current liabilities, net				5,531,000
Total				(36,562,000)
Adjustment for Error Correction, Reclassification [Member]
Net income (loss)				0
Depreciation, depletion and amortization				0
Equity in net income from unconsolidated joint ventures				(31,201,000)
Costs and estimated earnings in excess of billings, net				11,705,000
Equity in construction joint ventures				42,336,000
Contributions to unconsolidated construction joint ventures				16,209,000
Distributions from unconsolidated construction joint ventures				42,486,000
Other assets, net				0
Increase (Decrease) in Accounts Payable				(1,176,000)
Accrued expenses and other current liabilities, net				(24,531,000)
Total				$ 0