REVENUE - Disaggregation of revenue, geographical (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Lease revenue	$ 45.0	$ 32.8
Total revenue	1,555.8	1,632.0
Services
Disaggregation of Revenue [Line Items]
Revenue	896.7	826.2
Products
Disaggregation of Revenue [Line Items]
Revenue	614.1	773.0
Subsea
Disaggregation of Revenue [Line Items]
Revenue	1,289.1	1,386.5
Lease revenue	12.0	11.3
Subsea \| Operating Segments
Disaggregation of Revenue [Line Items]
Total revenue	1,289.1	1,386.5
Subsea \| Services
Disaggregation of Revenue [Line Items]
Revenue	845.6	793.4
Subsea \| Products
Disaggregation of Revenue [Line Items]
Revenue	431.5	581.8
Subsea \| Europe and Central Asia
Disaggregation of Revenue [Line Items]
Revenue	356.0	268.4
Subsea \| North America
Disaggregation of Revenue [Line Items]
Revenue	200.4	230.1
Subsea \| Latin America
Disaggregation of Revenue [Line Items]
Revenue	324.8	320.8
Subsea \| Asia Pacific
Disaggregation of Revenue [Line Items]
Revenue	221.5	245.0
Subsea \| Africa
Disaggregation of Revenue [Line Items]
Revenue	183.1	295.3
Subsea \| Middle East
Disaggregation of Revenue [Line Items]
Revenue	3.3	26.9
Surface Technologies
Disaggregation of Revenue [Line Items]
Revenue	266.7	245.5
Lease revenue	33.0	21.5
Surface Technologies \| Operating Segments
Disaggregation of Revenue [Line Items]
Total revenue	266.7	245.5
Surface Technologies \| Services
Disaggregation of Revenue [Line Items]
Revenue	51.1	32.8
Surface Technologies \| Products
Disaggregation of Revenue [Line Items]
Revenue	182.6	191.2
Surface Technologies \| Europe and Central Asia
Disaggregation of Revenue [Line Items]
Revenue	39.2	43.8
Surface Technologies \| North America
Disaggregation of Revenue [Line Items]
Revenue	116.2	74.5
Surface Technologies \| Latin America
Disaggregation of Revenue [Line Items]
Revenue	21.6	17.9
Surface Technologies \| Asia Pacific
Disaggregation of Revenue [Line Items]
Revenue	23.6	24.5
Surface Technologies \| Africa
Disaggregation of Revenue [Line Items]
Revenue	8.5	9.6
Surface Technologies \| Middle East
Disaggregation of Revenue [Line Items]
Revenue	$ 57.6	$ 75.2

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Amount of lease income from operating, direct financing, and sales-type leases. Includes, but is not limited to, variable lease payments, interest income, profit (loss) recognized at commencement, and lease payments paid and payable to lessor.

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