Summary of Significant Accounting Pronouncements (Details) (USD $)	3 Months Ended		12 Months Ended
	Dec. 31, 2010		Dec. 31, 2011 Y		Dec. 31, 2010		Dec. 31, 2009	Dec. 31, 2008
Significant Accounting Policies [Line Items]
Completion Percentage Upon Which Revenue Will Begin To Be Recognized			25.00%
Cash and cash equivalents	$ 252,022,000		$ 256,990,000		$ 252,022,000		$ 338,956,000	$ 460,843,000
Capitalized Computer Software, Additions			14,000,000		7,700,000		3,400,000
Finite-Lived Intangible Assets, Useful Life, Minimum			5
Finite-Lived Intangible Assets, Useful Life, Maximum			30
Goodwill and Intangible Asset Impairment			0		0		0
Standard Product Warranty Period In Years, Minimum			0.5
Standard Product Warranty Period In Years, Maximum			1.0
Extended Product Warranty Period In Years, Minimum			2.0
Extended Product Warranty Period In Years, Maximum			10.0
Restructuring charges	107,300,000		2,181,000		109,279,000		9,453,000
Minimum [Member]
Significant Accounting Policies [Line Items]
Amount Generally Liable Per Insurance Claim			500,000
Maximum [Member]
Significant Accounting Policies [Line Items]
Amount Generally Liable Per Insurance Claim			1,000,000
Accelerated Method [Member] | Equipment [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life, Minimum			3
Property, Plant and Equipment, Useful Life, Maximum			7
Straight Line Method [Member] | All Other Assets [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life, Minimum			3
Property, Plant and Equipment, Useful Life, Maximum			20
Consolidated Construction Joint Venture [Member] | Joint Venture Consolidated [Member]
Significant Accounting Policies [Line Items]
Cash and cash equivalents	$ 109,380,000	[1]	$ 75,122,000	[1]	$ 109,380,000	[1]

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