RENTALS AND LEASES - Lessor (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Property Subject to or Available for Operating Lease
Property, plant and equipment, gross	$ 6,667.5	$ 6,127.3
Accumulated depreciation	3,439.2	$ 3,040.2
Operating Leases, Income Statement, Lease Revenue
Operating lease revenue	412.7
Operating Leases, Future Minimum Payments Receivable
2020	357.0
2021	273.0
2022	208.0
2023	134.0
2024	55.0
Thereafter	16.0
Total lease revenue	1,043.0
Operating Leases Recorded in Property, Plant and Equipment
Property Subject to or Available for Operating Lease
Property, plant and equipment, gross	1,091.7
Accumulated depreciation	$ 606.7

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of lease payments to be received by lessor for operating lease.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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