Construction Joint Ventures - Schedule of Unconsolidated Construction Joint Ventures Assets and Liabilities (Details) - USD ($) $ in Thousands		Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017
Construction Joint Venture
Unconsolidated Construction Joint Venture Assets, Noncurrent Assets		$ 211,963	$ 219,825	$ 230,633
Equity in Construction Joint Ventures	[1]	237,731	231,887	214,526
Other Partners Interest in Partnerships [Member]
Construction Joint Venture
Unconsolidated Construction Joint Venture Assets		792,567	869,782	828,237
Unconsolidated Construction Joint Venture Liabilities	[2]	342,760	462,159	460,052
Reporting Entitys Interest in Joint Venture [Member]
Construction Joint Venture
Unconsolidated Construction Joint Venture Assets	[3],[4]	430,671	452,560	423,104
Unconsolidated Construction Joint Venture Liabilities		192,940	220,673	208,578
Cash and Cash Equivalents [Member]
Construction Joint Venture
Unconsolidated Construction Joint Venture Assets		309,330	289,940	388,542
Other Assets, Current and Longterm [Member]
Construction Joint Venture
Unconsolidated Construction Joint Venture Assets	[3]	701,945	812,577	632,166
Accounts Payable [Member]
Construction Joint Venture
Unconsolidated Construction Joint Venture Liabilities		$ 535,700	$ 682,832	$ 668,630

[1] 4Included in this balance and in accrued expenses and other current liabilities on the condensed consolidated balance sheets were amounts related to deficits in construction joint ventures that were $14.7 million as of June 30, 2018 and $15.9 million as of both December 31, 2017 and June 30, 2017

[2] 3Partners’ interest and adjustments includes amounts to reconcile total net assets as reported by our partners to Granite’s interest adjusted to reflect our accounting policies and estimates primarily related to contract forecast differences.

[3] 1Included in this balance and in accrued expenses and other current liabilities on our condensed consolidated balance sheets were amounts related to performance guarantees that were $88.6 million as of both June 30, 2018 and December 31, 2017 and $88.9 million as of June 30, 2017.

[4] 2Included in this balance as of June 30, 2018, December 31, 2017 and June 30, 2017 was $65.8 million, $74.3 million and $81.7 million, respectively, related to Granite’s share of estimated cost recovery of customer affirmative claims. In addition, this balance included $10.6 million, $11.8 million and $9.8 million related to Granite’s share of estimated recovery of back charge claims as of June 30, 2018, December 31, 2017 and June 30, 2017, respectively.