Operations by Business Segment and Geographical Area (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Operations by Business Segment and Geographical Area
Total external revenue	$ 7,185,624,000	$ 6,290,108,000
Total segment profit (loss)	293,600,000	253,300,000
Total assets	8,463,034,000		8,276,043,000
Oil and Gas Segment
Operations by Business Segment and Geographical Area
Total external revenue	2,769,300,000	2,040,800,000
Total segment profit (loss)	104,500,000	73,400,000
Total assets	1,785,900,000		1,704,400,000
Industrial and Infrastructure Segment
Operations by Business Segment and Geographical Area
Total external revenue	3,132,200,000	3,041,700,000
Total segment profit (loss)	126,900,000	113,500,000
Total assets	900,800,000		751,700,000
Government Segment
Operations by Business Segment and Geographical Area
Total external revenue	751,200,000	850,100,000
Total segment profit (loss)	41,300,000	35,300,000
Total assets	893,600,000		827,200,000
Global Services Segment
Operations by Business Segment and Geographical Area
Total external revenue	149,900,000	182,600,000
Intercompany revenue	117,200,000	115,600,000
Total segment profit (loss)	27,700,000	33,000,000
Total assets	775,600,000		768,900,000
Power Segment
Operations by Business Segment and Geographical Area
Total external revenue	383,000,000	174,900,000
Total segment profit (loss)	(6,800,000)	(1,900,000)
Total assets	154,900,000		120,600,000
Research and development expense	$ 15,000,000	$ 10,300,000