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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of lessee's right to use underlying asset under 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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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Leases - Balance sheet by asset category (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Apr. 01, 2018
Lessee, Lease, Description [Line Items]
Operating lease ROU Asset	$ 31.2
Property, plant and equipment, gross	539.2	$ 537.4
Less: Accumulated depreciation	(339.6)	(335.5)
Property, plant and equipment, net	199.6	$ 201.9	$ 201.1
Finance Leased Asset
Lessee, Lease, Description [Line Items]
Less: Accumulated depreciation	(8.1)
Property, plant and equipment, net	10.1
Finance Leased Real Estate
Lessee, Lease, Description [Line Items]
Property, plant and equipment, gross	14.5
Finance Leased Machinery and Equipment
Lessee, Lease, Description [Line Items]
Property, plant and equipment, gross	3.7
Real Estate
Lessee, Lease, Description [Line Items]
Operating lease ROU Asset	24.4
Automobile
Lessee, Lease, Description [Line Items]
Operating lease ROU Asset	3.3
Machinery and equipment
Lessee, Lease, Description [Line Items]
Operating lease ROU Asset	$ 3.5