Note 11 - Construction Joint Ventures - Schedule of Unconsolidated Construction Joint Ventures Revenue and Costs (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Cost of revenue		$ 889,439	$ 942,194	$ 2,236,169	$ 2,396,015
Decrease to net income/increase to net loss		69,289	32,423	76,036	22,847
Granite’s interest in net income (loss) (2)				(23,585)	8,027
Collaborative Arrangement [Member]
Revenue		25,355	81,281	98,200	247,904
Cost of revenue		31,812	80,325	121,346	240,114
Granite’s interest in gross profit (loss)		(6,457)	956	(23,146)	7,790
Granite’s interest in net income (loss) (2)	[1]	(6,357)	1,056	(23,585)	8,027
Collaborative Arrangement [Member] | Corporate Joint Venture [Member]
Revenue		69,355	194,486	322,058	690,086
Cost of revenue		81,694	203,786	332,777	701,350
Decrease to net income/increase to net loss		(11,945)	(9,279)	(11,649)	(11,469)
Collaborative Arrangement [Member] | Co-venturer [Member] | Other Partners Interest in Partnerships [Member]
Revenue	[2]	44,000	113,205	223,858	442,182
Cost of revenue	[2]	49,882	123,461	211,431	461,236
Decrease to net income/increase to net loss	[2]	$ (5,588)	$ (10,335)	$ 11,936	$ (19,496)

[1] These joint venture net income/(loss) amounts exclude our corporate overhead required to manage the joint ventures and include taxes only to the extent the applicable states have joint venture level taxes.

[2] 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 and/or actual differences.