Goodwill And Intangible Assets (Carrying Amount of Goodwill) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Beginning balance	$ 3,718.3	$ 3,786.5	$ 4,114.2
Additions due to business combinations	5,165.9	0.0	41.9
Impairment	0.0	0.0	0.0
Translation	45.6	(68.2)	(369.6)
Ending balance	8,929.8	3,718.3	3,786.5
Subsea
Goodwill [Roll Forward]
Beginning balance	2,931.1	2,977.4	3,232.0
Additions due to business combinations	2,532.6	0.0	41.9
Impairment	0.0	0.0	0.0
Translation	6.7	(46.3)	(296.5)
Ending balance	5,470.4	2,931.1	2,977.4
Onshore/Offshore
Goodwill [Roll Forward]
Beginning balance	787.2	809.1	882.2
Additions due to business combinations	1,635.5	0.0	0.0
Impairment	0.0	0.0	0.0
Translation	38.9	(21.9)	(73.1)
Ending balance	2,461.6	787.2	809.1
Surface Technologies
Goodwill [Roll Forward]
Beginning balance	0.0	0.0	0.0
Additions due to business combinations	997.8	0.0	0.0
Impairment	0.0	0.0	0.0
Translation	0.0	0.0	0.0
Ending balance	$ 997.8	$ 0.0	$ 0.0

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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