Business Segments (Schedule Of Segment Revenue And Segment Operating Profit) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information
Revenue	$ 3,143.8	$ 4,140.9	$ 9,229.9	$ 11,373.9
Total segment operating profit	375.0	358.2	961.6	976.2
Corporate expense	(68.1)	(42.3)	(200.9)	(224.3)
Net interest expense	(106.0)	(86.3)	(244.3)	(240.5)
Total corporate items	(174.1)	(128.6)	(445.2)	(464.8)
Income before income taxes	200.9	229.6	516.4	511.4
Subsea
Segment Reporting Information
Revenue	1,209.1	1,478.2	3,606.7	4,585.2
Total segment operating profit	79.7	102.8	210.0	393.1
Onshore/Offshore
Segment Reporting Information
Revenue	1,532.5	2,308.1	4,448.3	5,885.0
Total segment operating profit	243.4	206.4	617.6	553.7
Surface Technologies
Segment Reporting Information
Revenue	402.2	353.9	1,174.9	902.3
Total segment operating profit	$ 51.9	49.0	$ 134.0	29.4
Other revenue
Segment Reporting Information
Revenue		$ 0.7		$ 1.4

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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