CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (93,961)	$ (6,081)	$ (125,042)	$ (15,743)
Other comprehensive loss, net of tax:
Net unrealized loss on derivatives	(2,178)	(1,354)	(2,776)	(734)
Less: reclassification for net (gains) loss included in interest expense	(117)	1,602	(290)	1,562
Net change	(2,295)	248	(3,066)	828
Foreign currency translation adjustments, net	(527)	(421)	367	(438)
Other comprehensive (loss) income	(2,822)	(173)	(2,699)	390
Comprehensive loss	(96,783)	(6,254)	(127,741)	(15,353)
Non-controlling interests in comprehensive loss	(3,875)	(2,304)	(7,368)	(4,065)
Comprehensive loss attributable to Granite Construction Incorporated	$ (100,658)	$ (8,558)	$ (135,109)	$ (19,418)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount, after tax and reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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