CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net (loss) income	$ (6,081)	$ 16,272	$ (15,743)	$ (7,579)
Other comprehensive income (loss), net of tax:
Net unrealized loss on derivatives	(1,354)	(261)	(734)	(209)
Less: reclassification for net losses included in interest expense	1,602	47	1,562	116
Net change	248	(214)	828	(93)
Foreign currency translation adjustments, net	(421)	542	(438)	535
Other comprehensive (loss) income	(173)	328	390	442
Comprehensive (loss) income	(6,254)	16,600	(15,353)	(7,137)
Non-controlling interests in comprehensive loss	(2,304)	(2,139)	(4,065)	(2,078)
Comprehensive (loss) income attributable to Granite	$ (8,558)	$ 14,461	$ (19,418)	$ (9,215)

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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