Construction and Line Item Joint Ventures - Unconsolidated Construction Joint Ventures (Details) (USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012		Dec. 31, 2012
Construction Joint Venture [Line Items]
Equity in construction joint ventures	$ 161,063,000		$ 97,890,000		$ 161,063,000		$ 97,890,000		$ 105,805,000
Equity in Construction Joint Ventures Current Assets Excluding Deficit in Equity	161,063,000				161,063,000				105,805,000
Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Number of Active Joint Venture Projects	5				5
Partnership Interest [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	5,000,000,000				5,000,000,000
Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Number of Active Joint Venture Projects	4				4
Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Number of Active Joint Venture Projects	11				11
Unconsolidated Construction Joint Venture Revenue	363,523,000		286,308,000		848,082,000		776,235,000
Unconsolidated Construction Joint Venture Cost of Revenue	290,112,000		200,688,000		661,587,000		597,689,000
Reporting Entitys Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Assets	294,304,000		224,748,000		294,304,000		224,748,000		203,553,000
Unconsolidated Construction Joint Venture Liabilities	133,241,000		126,858,000		133,241,000		126,858,000		97,748,000
Unconsolidated Construction Joint Venture Revenue	103,868,000		104,629,000		262,066,000		278,492,000
Unconsolidated Construction Joint Venture Cost of Revenue	86,308,000		70,848,000		208,803,000		208,518,000
Unconsolidated Construction Joint Venture Gross Profit Loss	17,560,000		33,781,000		53,263,000		69,974,000
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	1,400,000,000				1,400,000,000
Other Partners Interest in Partnerships [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Assets	557,857,000		353,165,000		557,857,000		353,165,000		342,545,000
Unconsolidated Construction Joint Venture Liabilities	336,885,000		219,807,000		336,885,000		219,807,000		183,432,000
Unconsolidated Construction Joint Venture Revenue	259,655,000	[1]	181,679,000	[1]	586,016,000	[1]	497,743,000	[1]
Unconsolidated Construction Joint Venture Cost of Revenue	203,804,000	[1]	129,840,000	[1]	452,784,000	[1]	389,171,000	[1]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	3,600,000,000				3,600,000,000
Minimum [Member] | Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	400,000				400,000
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	51.00%				51.00%
Minimum [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	40,000,000				40,000,000
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	20.00%				20.00%
Minimum [Member] | Joint Venture Unconsolidated [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	42,200,000				42,200,000
Revenue Per Project Remaining to be Recognized on Line Item Construction Joint Ventures	100,000				100,000
Minimum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	200,000				200,000
Minimum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	23,000,000				23,000,000
Maximum [Member] | Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	336,900,000				336,900,000
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	65.00%				65.00%
Maximum [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	3,100,000,000				3,100,000,000
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	50.00%				50.00%
Maximum [Member] | Joint Venture Unconsolidated [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	138,600,000				138,600,000
Revenue Per Project Remaining to be Recognized on Line Item Construction Joint Ventures	23,800,000				23,800,000
Maximum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	691,000,000				691,000,000
Maximum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	60,800,000				60,800,000
Cash and Cash Equivalents [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Assets	412,506,000	[2]	304,065,000	[2]	412,506,000	[2]	304,065,000	[2]	244,686,000	[2]
Other Assets, Current and Longterm [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Assets	439,655,000		273,848,000		439,655,000		273,848,000		301,412,000
Accounts Payable [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Liabilities	127,695,000		94,788,000		127,695,000		94,788,000		114,039,000
Billings in Excess of Costs and Estimated Earnings [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Liabilities	274,052,000	[2]	243,578,000	[2]	274,052,000	[2]	243,578,000	[2]	161,268,000	[2]
Accrued Liabilities [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Liabilities	$ 68,379,000		$ 8,299,000		$ 68,379,000		$ 8,299,000		$ 5,873,000

[1] Partners’ interest represents amounts to reconcile total revenue and total cost of revenue as reported by our partners to Granite’s interest, adjusted to reflect our accounting policies.

[2] The volume and stage of completion of contracts from our unconsolidated construction joint ventures may cause fluctuations in cash and cash equivalents, as well as billings in excess of costs and estimated earnings between periods. The decision to distribute joint venture cash and cash equivalents and assets must generally be made jointly by all of the partners and, accordingly, these cash and cash equivalents and assets generally are not available for the working capital needs of Granite until distributed.