Goodwill And Intangible Assets (Carrying Amount of Goodwill) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Asset Impairment Charges	$ 2,484.1	$ 1,792.6	$ 34.3
Goodwill [Roll Forward]
Beginning balance	7,607.6	8,929.8	3,718.3
Additions due to business combinations		85.0	5,165.9
Impairment	(1,988.7)	(1,383.0)
Goodwill, Purchase Accounting Adjustments	9.9	19.7
Goodwill, Other Increase (Decrease)	(17.7)
Translation	(12.8)	(43.9)	45.6
Ending balance	$ 5,598.3	7,607.6	8,929.8
Current Fiscal Year End Date	--12-31
Subsea
Goodwill [Line Items]
Asset Impairment Charges	$ 1,798.6	1,784.2	11.5
Goodwill [Roll Forward]
Beginning balance	4,142.4	5,470.4	2,931.1
Additions due to business combinations		85.0	2,532.6
Impairment	1,321.9	(1,383.0)
Translation	(6.4)	(30.0)	6.7
Ending balance	2,814.1	4,142.4	5,470.4
Onshore/Offshore
Goodwill [Roll Forward]
Beginning balance	2,447.7	2,461.6	787.2
Additions due to business combinations			1,635.5
Impairment	0.0
Goodwill, Other Increase (Decrease)	(17.7)
Translation	(6.4)	(13.9)	38.9
Ending balance	2,423.6	2,447.7	2,461.6
Surface Technologies
Goodwill [Line Items]
Asset Impairment Charges	685.5	4.5	10.2
Goodwill [Roll Forward]
Beginning balance	1,017.5	997.8
Additions due to business combinations			997.8
Impairment	(666.8)
Goodwill, Purchase Accounting Adjustments	9.9	19.7
Ending balance	$ 360.6	$ 1,017.5	$ 997.8

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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