Commitments and Contingencies - Operating Lease Commitments (Details) $ in Millions	Dec. 31, 2019 USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2018	$ 6.4
2019	6.1
2020	5.6
2021	5.2
2022	5.1
Thereafter	22.1
Operating leases, future minimum payments due	50.5
Third Parties
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2018	5.0
2019	4.7
2020	4.4
2021	4.2
2022	4.1
Thereafter	20.5
Operating leases, future minimum payments due	42.9
Related Entity
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2018	1.4
2019	1.4
2020	1.2
2021	1.0
2022	1.0
Thereafter	1.6
Operating leases, future minimum payments due	$ 7.6

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth 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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