Construction and Line Item Joint Ventures - Unconsolidated Construction Joint Ventures (Details) (USD $)	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011		Dec. 31, 2011
Construction Joint Venture [Line Items]
Equity in construction joint ventures	$ 91,951,000		$ 78,773,000		$ 101,029,000
Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Number of Active Joint Venture Projects	4
Partnership Interest [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	2,200,000,000
Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Number of Active Joint Venture Projects	2
Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Number of Active Joint Venture Projects	9
Unconsolidated Construction Joint Venture Revenue	205,832,000		199,768,000
Unconsolidated Construction Joint Venture Cost of Revenue	169,612,000		150,880,000
Reporting Entitys Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Assets	216,227,000		209,781,000		238,603,000
Unconsolidated Construction Joint Venture Liabilities	124,276,000		131,008,000		137,574,000
Unconsolidated Construction Joint Venture Revenue	73,629,000		73,422,000
Unconsolidated Construction Joint Venture Cost of Revenue	60,372,000		49,016,000
Unconsolidated Construction Joint Venture Gross Profit Loss	13,257,000		24,406,000
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	800,000,000
Other Partners Interest in Partnerships [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Assets	362,474,000		325,454,000		364,979,000
Unconsolidated Construction Joint Venture Liabilities	220,284,000		232,673,000		236,746,000
Unconsolidated Construction Joint Venture Revenue	132,203,000	[1]	126,346,000	[1]
Unconsolidated Construction Joint Venture Cost of Revenue	109,240,000	[1]	101,864,000	[1]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	1,400,000,000
Minimum [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Per Project Remaining to be Recognized on Line Item Construction Joint Ventures	6,800,000
Minimum [Member] | Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	235,900,000
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	45.00%
Minimum [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	57,800,000
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	20.00%
Minimum [Member] | Joint Venture Unconsolidated [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	52,100,000
Minimum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	2,800,000
Minimum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	21,400,000
Maximum [Member] | Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	317,500,000
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	60.00%
Maximum [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	1,200,000,000
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	50.00%
Maximum [Member] | Joint Venture Unconsolidated [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	128,300,000
Revenue Per Project Remaining to be Recognized on Line Item Construction Joint Ventures	37,000,000
Maximum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	242,200,000
Maximum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	53,600,000
Cash and Cash Equivalents [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Assets	341,989,000		331,169,000		338,681,000
Other Assets, Current and Longterm [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Assets	236,712,000		204,066,000		264,901,000
Accounts Payable [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Liabilities	98,872,000		76,009,000		85,075,000
Billings in Excess of Costs and Estimated Earnings [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Liabilities	240,043,000		278,132,000		280,650,000
Accrued Liabilities [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Unconsolidated Construction Joint Venture Liabilities	$ 5,645,000		$ 9,540,000		$ 8,595,000

[1] The volume and stage of completion of contracts from our unconsolidated construction joint ventures may cause fluctuations in cash and cash equivalents, as well as billings in excess of costs and estimated earnings between periods.