Goodwill And Intangible Assets (Carrying Amount of Goodwill) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Roll Forward]
Beginning balance	$ 8,929.8	$ 3,718.3	$ 3,786.5
Additions due to business combinations	85.0	5,165.9
Impairment	(1,383.0)
Goodwill, Purchase Accounting Adjustments	19.7
Translation	(43.9)	45.6	(68.2)
Ending balance	7,607.6	8,929.8	3,718.3
Subsea
Goodwill [Roll Forward]
Beginning balance	5,470.4	2,931.1	2,977.4
Additions due to business combinations	85.0	2,532.6
Impairment	1,383.0
Translation	(30.0)	6.7	(46.3)
Ending balance	4,142.4	5,470.4	2,931.1
Onshore/Offshore
Goodwill [Roll Forward]
Beginning balance	2,461.6	787.2	809.1
Additions due to business combinations		1,635.5
Translation	(13.9)	38.9	(21.9)
Ending balance	2,447.7	2,461.6	$ 787.2
Surface Technologies
Goodwill [Roll Forward]
Beginning balance	997.8
Additions due to business combinations		997.8
Goodwill, Purchase Accounting Adjustments	19.7
Ending balance	$ 1,017.5	$ 997.8

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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