Construction Joint Ventures - Schedule of Unconsolidated Construction Joint Ventures Revenue and Costs (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Revenue		$ 449,996	$ 515,983	$ 689,437	$ 967,304
Unconsolidated Construction Joint Venture Cost of Revenue		423,385	498,932	804,274	941,922
Unconsolidated Construction Joint Venture Gross Loss		(17,948)	(9,724)	(13,927)	(8,228)
Other Partners Interest in Partnerships [Member]
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Revenue	[1]	340,809	376,332	461,841	700,162
Unconsolidated Construction Joint Venture Cost of Revenue	[1]	296,250	349,557	562,751	666,552
Reporting Entitys Interest in Joint Venture [Member]
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Revenue		109,187	139,651	227,596	267,142
Unconsolidated Construction Joint Venture Cost of Revenue		$ 127,135	$ 149,375	$ 241,523	$ 275,370

[1] 1Partners’ 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 and estimates.