Construction Joint Ventures - Additional Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018 USD ($) project	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) project	Jun. 30, 2017 USD ($)
Construction Joint Venture
Number of active construction joint venture projects | project	10		10
Construction Contract Value	$ 12,200,000		$ 12,200,000
Revenue	807,119	$ 762,913	1,370,498	$ 1,231,313
Net cash provided by operating activities			(75,445)	22,686
Unconsolidated Construction Joint Venture Net (Loss) Income	$ (26,500)	17,600	$ (114,400)	26,200
Line Item Joint Venture [Member]
Construction Joint Venture
Number of active construction joint venture projects | project	1		1
Revenue	$ 400	6,800	$ 1,200	14,700
Line Item Joint Venture One [Member]
Construction Joint Venture
Construction Contract Value	18,000		18,000
Minimum [Member]
Construction Joint Venture
Construction Contract Value	$ 77,300		$ 77,300
Proportionate Share of the Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	20.00%		20.00%
Maximum [Member]
Construction Joint Venture
Construction Contract Value	$ 3,700,000		$ 3,700,000
Proportionate Share of the Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	50.00%		50.00%
Reporting Entitys Interest in Joint Venture [Member]
Construction Joint Venture
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	$ 1,300,000		$ 1,300,000
Other Partners Interest in Partnerships [Member]
Construction Joint Venture
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	$ 2,600,000		$ 2,600,000
Joint Venture Consolidated [Member]
Construction Joint Venture
Number of active construction joint venture projects | project	6		6
Construction Contract Value	$ 1,200,000		$ 1,200,000
Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture
Revenue	67,700	49,500	111,500	85,000
Net cash provided by operating activities			15,100	19,200
Joint Venture Consolidated [Member] | Minimum [Member]
Construction Joint Venture
Construction Contract Value	$ 50,500		$ 50,500
Joint Venture Consolidated [Member] | Minimum [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture
Proportionate Share of the Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	50.00%		50.00%
Joint Venture Consolidated [Member] | Maximum [Member]
Construction Joint Venture
Construction Contract Value	$ 409,700		$ 409,700
Joint Venture Consolidated [Member] | Maximum [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture
Proportionate Share of the Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	65.00%		65.00%
Partnership Interest [Member]
Construction Joint Venture
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	$ 3,900,000		$ 3,900,000
Granite Construction [Member]
Construction Joint Venture
Revenue			1,300,000
Unconsolidated Construction Joint Venture Net (Loss) Income	(17,700)	$ (9,700)	(13,400)	$ (8,200)
Granite Construction [Member] | Line Item Joint Venture One [Member]
Construction Joint Venture
Construction Contract Value	10,800		10,800
Revenue Remaining to be Recognized on Consolidated Construction Joint Ventures	$ 10,600		10,600
Granite Construction [Member] | Minimum [Member]
Construction Joint Venture
Revenue			2,300
Granite Construction [Member] | Maximum [Member]
Construction Joint Venture
Revenue			312,800
Granite Construction [Member] | Joint Venture Consolidated [Member]
Construction Joint Venture
Revenue			430,900
Granite Construction [Member] | Joint Venture Consolidated [Member] | Minimum [Member]
Construction Joint Venture
Revenue			1,100
Granite Construction [Member] | Joint Venture Consolidated [Member] | Maximum [Member]
Construction Joint Venture
Revenue			$ 190,800