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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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The minimum amount the entity agreed to spend under the long-term purchase commitment.

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Period covered by the long-term purchase commitment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of operating lease expense. Excludes sublease income.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Commitments (Details) - USD ($) $ in Millions	12 Months Ended
Commitments (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Expected future rental payments under operating leases in 2020	$ 14.9
Expected future rental payments under operating leases in 2021	14.3
Expected future rental payments under operating leases in 2022	13.5
Expected future rental payments under operating leases in 2023	13.0
Expected future rental payments under operating leases in 2024	12.2
Rental expense for noncancelable operating leases	$ 21.6
Rental expense for noncancelable operating leases		$ 15.2	$ 14.0
Take-Or-Pay Contracts
Other Commitments [Line Items]
Term of take-or-pay contract	1 year 8 months 12 days
Take-or-pay contract due in 2020	$ 7.9
Take-or-pay contract due in 2021	4.9
Capital Addition Purchase Commitments
Other Commitments [Line Items]
Commitments for capital expenditures	246.9
Construction in Progress
Other Commitments [Line Items]
Commitments for capital expenditures	202.9
Building Improvements
Other Commitments [Line Items]
Commitments for capital expenditures	$ 39.2