Business Segments (Segment Operating Capital Employed And Segment Assets) (Details) - USD ($) $ in Millions		Sep. 30, 2017	Dec. 31, 2016
Segment Reporting Information
Total assets		$ 29,628.2	$ 18,689.7
Operating segments
Segment Reporting Information
Total assets		21,268.7	11,052.4
Operating segments | Subsea
Segment Reporting Information
Total assets		13,757.6	7,823.1
Operating segments | Onshore/Offshore
Segment Reporting Information
Total assets		5,114.5	3,229.3
Operating segments | Surface Technologies
Segment Reporting Information
Total assets		2,413.6
Intercompany eliminations
Segment Reporting Information
Total assets		(17.0)
Corporate
Segment Reporting Information
Total assets	[1]	$ 8,359.5	$ 7,637.3

[1] Corporate includes cash, LIFO adjustments, deferred income tax balances, property, plant and equipment not associated with a specific segment, pension assets and the fair value of derivative financial instruments.