Construction and Line Item Joint Ventures - Schedule of Unconsolidated Construction Joint Ventures Assets and Liabilities (Details) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Construction Joint Venture [Line Items]
Deficit in unconsolidatedconstruction joint venture		$ 8,200	$ 800	$ 8,200	$ 800	$ 8,600
Equity in Construction Joint Ventures Current Assets Excluding Deficit in Equity	[1]	237,298	208,248	237,298	208,248	216,063
Granite Construction [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Revenue		(2,900)	7,300	5,600	18,600
Partnership Interest [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures		$ 5,100,000		$ 5,100,000
Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Number of Active Joint Venture Projects		5		5
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		$ 682,002	466,144	$ 970,046	909,551
Unconsolidated Construction Joint Venture Cost of Revenue		479,113	436,230	940,610	846,301
Unconsolidated Construction Joint Venture Revenue		$ (4,400)	34,000	$ 29,300	67,400
Joint Venture Unconsolidated [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Number of Active Joint Venture Projects		6		6
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		$ 1,600,000		$ 1,600,000
Unconsolidated Construction Joint Venture Assets		437,723	380,968	437,723	380,968	418,437
Unconsolidated Construction Joint Venture Liabilities		200,425	172,720	200,425	172,720	202,374
Unconsolidated Construction Joint Venture Revenue		129,016	138,164	275,275	273,451
Unconsolidated Construction Joint Venture Cost of Revenue		131,452	130,408	268,908	254,432
Unconsolidated Construction Joint Venture Gross Profit Loss		(2,436)	7,756	6,367	19,019
Other Partners Interest in Partnerships [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures		3,500,000		3,500,000
Unconsolidated Construction Joint Venture Assets		894,017	771,875	894,017	771,875	881,183
Unconsolidated Construction Joint Venture Liabilities		434,371	385,506	434,371	385,506	447,926
Unconsolidated Construction Joint Venture Revenue	[2]	552,986	327,980	694,771	636,100
Unconsolidated Construction Joint Venture Cost of Revenue	[2]	347,661	305,822	671,702	591,869
Minimum [Member] | Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value		$ 6,700		$ 6,700
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly		50.00%		50.00%
Minimum [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value		$ 80,200		$ 80,200
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		$ 42,200
Revenue Per Project Remaining to be Recognized on Line Item Construction Joint Ventures		100		100
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		300		300
Minimum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value		24,800		24,800
Maximum [Member] | Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value		$ 290,900		$ 290,900
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		$ 3,600,000		$ 3,600,000
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		$ 87,800		$ 87,800
Revenue Per Project Remaining to be Recognized on Line Item Construction Joint Ventures		29,300		29,300
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		566,300		566,300
Maximum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value		64,900		64,900
Cash and Cash Equivalents [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Assets		435,098	336,581	435,098	336,581	439,871
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		896,642	816,262	896,642	816,262	859,749
Accounts Payable [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Liabilities		254,954	216,663	254,954	216,663	218,790
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		277,900	276,982	277,900	276,982	341,609
Accrued Liabilities [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Liabilities		$ 101,942	$ 64,581	$ 101,942	$ 64,581	$ 89,901

[1] As of June 30, 2016, December 31, 2015 and June 30, 2015 this balance included $8.2 million, $8.6 million and $0.8 million, respectively, of deficit in construction joint ventures that is included in accrued expenses and other current liabilities on the condensed consolidated balance sheets.

[2] 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.