Business Segments (Other Business Segment Information) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Capital expenditures	$ 454.4	$ 368.1	$ 255.7
Depreciation and amortization	509.6	550.4	614.7
Research and development expense	162.9	189.2	212.9
Operating segments \| Subsea
Segment Reporting Information [Line Items]
Capital expenditures	287.7	223.2	179.1
Depreciation and amortization	345.6	440.4	507.2
Research and development expense	134.4	145.2	169.2
Operating segments \| Onshore/Offshore
Segment Reporting Information [Line Items]
Capital expenditures	22.6	7.6	16.2
Depreciation and amortization	38.7	38.2	41.1
Research and development expense	13.2	29.7	31.4
Operating segments \| Surface Technologies
Segment Reporting Information [Line Items]
Capital expenditures	96.6	111.9	35.4
Depreciation and amortization	107.9	66.6	63.6
Research and development expense	15.3	14.3	12.3
Corporate
Segment Reporting Information [Line Items]
Capital expenditures	47.5	25.4	25.0
Depreciation and amortization	$ 17.4	$ 5.2	$ 2.8

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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