Construction Joint Ventures - Schedule of Unconsolidated Construction Joint Ventures Revenue and Costs (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Revenue		$ 1,544,406	$ 2,057,336	$ 1,958,158
Unconsolidated Construction Joint Venture Cost of Revenue		1,787,501	1,995,915	1,915,376
Unconsolidated Construction Joint Venture Gross (Loss) Profit		(25,330)	(13,782)	15,709
Other Partners Interest in Partnerships [Member]
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Revenue	[1]	1,022,370	1,469,550	1,387,532
Unconsolidated Construction Joint Venture Cost of Revenue	[1]	1,240,135	1,394,347	1,360,459
Reporting Entitys Interest in Joint Venture [Member]
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Revenue		522,036	587,786	570,626
Unconsolidated Construction Joint Venture Cost of Revenue		$ 547,366	$ 601,568	$ 554,917

[1] Partners’ interest and adjustments includes 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 primarily related to contract forecast differences.