Construction Joint Ventures - Schedule of Unconsolidated Construction Joint Ventures Revenue and Costs (Details) - USD ($) $ in Thousands		3 Months Ended			6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016		Jun. 30, 2017	Jun. 30, 2016
Variable Interest Entity [Line Items]
Contracts Revenue		$ 429,269	$ 331,346		$ 656,118	$ 540,833
Total Unconsolidated JV and Partner's Interest in Revenue As reported			552,986
Total Unconsolidated JV Revenue As reported			682,002
Parent Company [Member] | Unconsolidated Construction Joint Venture
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Net (Loss) Income		(9,700)	(2,900)		(8,200)	5,600
Joint Venture Unconsolidated | Unconsolidated Construction Joint Venture
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Revenue		515,983	475,879	[1]	967,304	970,046
Unconsolidated Construction Joint Venture Cost of Revenue		498,932	479,113		941,922	940,610
Unconsolidated Construction Joint Venture Net (Loss) Income		17,600	(4,400)		26,200	29,300
Other Partners Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Revenue	[2]	376,332	346,863	[1]	700,162	694,771
Unconsolidated Construction Joint Venture Cost of Revenue	[2]	349,557	347,661	[1]	666,552	671,702
Reporting Entitys Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Revenue		139,651	129,016		267,142	275,275
Unconsolidated Construction Joint Venture Cost of Revenue		149,375	131,452		275,370	268,908
Unconsolidated Construction Joint Venture Gross (Loss) Profit		$ (9,724)	$ (2,436)		$ (8,228)	$ 6,367

[1] While Granite’s interest in revenue, cost of revenue and gross profit were correctly stated, Total revenue and revenue for partners’ interest and adjustments for the three months ended June 30, 2016 were misstated in our Quarterly Report for the quarter ended June 30, 2016. Total revenue and revenue for partner’s interest and adjustments as reported was (in thousands): $682,002 and $552,986, respectively, for the three months ended June 30, 2016. Total revenue and revenue for partner’s interest and adjustments should have been (in thousands): $475,879 and $346,863, respectively, for the three months ended June 30, 2016 and are reflected in the table. The misstatements did not have any impact on the consolidated financial statements in any period. We assessed the materiality of the errors in accordance with the SEC’s Staff Accounting Bulletin 99 and concluded that the errors were not material to either of these previously issued financial statements. Accordingly, we will revise our previously issued financial statements prospectively to correct these errors.

[2] Partners’ interest and adjustments 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.