Schedule of Unconsolidated Construction Joint Ventures Revenue and Costs (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Variable Interest Entity [Line Items]
Deficit in unconsolidatedconstruction joint venture	$ 800		$ 800
Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Revenue	466,144	$ 392,165	909,551	$ 741,331
Unconsolidated Construction Joint Venture Cost of Revenue	436,230	345,704	846,301	643,166
Other Partners Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture [Member]
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Revenue	327,980	268,526	636,100	528,383
Unconsolidated Construction Joint Venture Cost of Revenue	305,822	246,065	591,869	456,972
Reporting Entitys Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture [Member]
Variable Interest Entity [Line Items]
Unconsolidated Construction Joint Venture Revenue	138,164	123,639	273,451	212,948
Unconsolidated Construction Joint Venture Cost of Revenue	130,408	99,639	254,432	186,194
Unconsolidated Construction Joint Venture Gross Profit Loss	$ 7,756	$ 24,000	$ 19,019	$ 26,754