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Leases (Lease Maturity) (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
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Lease Maturity [Line Items] |  |
Total Future Minimum Lease Payments Due, Next Twelve Months | $ 44.4 |
Total Future Minimum Lease Payments, Due in Two Years | 37.4 |
Total Future Minimum Lease Payments, Due in Three Years | 33.5 |
Total Future Minimum Lease Payments, Due in Four Years | 25.3 |
Total Future Minimum Lease Payments, Due in Five Years | 19.8 |
Total Future Minimum Lease Payments, Due Thereafter | 152.3 |
Total Future Minimum Lease Payments Due | 312.7 |
Undiscounted Excess Amount | (77.5) |
Total Lease Liability | 235.2 | $ 266.3
Short-term Lease Liability | 33.6 |
Long-term Lease Liability | 201.6 |
Finance Leases, Future Minimum Payments Due, Next Twelve Months | 32.7 |
Finance Leases, Future Minimum Payments Due in Two Years | 32.2 |
Finance Leases, Future Minimum Payments Due in Three Years | 28.8 |
Finance Leases, Future Minimum Payments Due in Four Years | 20.8 |
Finance Leases, Future Minimum Payments Due in Five Years | 16.1 |
Finance Leases, Future Minimum Payments Due Thereafter | 134.1 |
Finance Lease, Liability, Payment, Due | 264.7 |
Finance Lease, Liability, Current | 23.3 | 13.4
Finance Lease, Liability, Noncurrent | 171.7 | 188.1
Operating Leases, Future Minimum Payments Due, Next Twelve Months | 11.7 |
Operating Leases, Future Minimum Payments, Due in Two Years | 5.2 |
Operating Leases, Future Minimum Payments, Due in Three Years | 4.7 |
Operating Leases, Future Minimum Payments, Due in Four Years | 4.5 |
Operating Leases, Future Minimum Payments, Due in Five Years | 3.7 |
Operating Leases, Future Minimum Payments, Due Thereafter | 18.2 |
Lessee, Operating Lease, Liability, Payments, Due | 48.0 |
Operating Lease, Liability, Current | 10.3 | 13.2
Operating Lease, Liability, Noncurrent | 29.9 | $ 51.6
Finance Lease |  |
Lease Maturity [Line Items] |  |
Finance Leases, Future Minimum Payments Due, Next Twelve Months | 32.7 |
Finance Leases, Future Minimum Payments Due in Two Years | 32.2 |
Finance Leases, Future Minimum Payments Due in Three Years | 28.8 |
Finance Leases, Future Minimum Payments Due in Four Years | 20.8 |
Finance Leases, Future Minimum Payments Due in Five Years | 16.1 |
Finance Leases, Future Minimum Payments Due Thereafter | 134.1 |
Finance Lease, Liability, Payment, Due | 264.7 |
Finance Lease, Liability, Undiscounted Excess Amount | (69.7) |
Finance Lease, Liability | 195.0 |
Finance Lease, Liability, Current | 23.3 |
Finance Lease, Liability, Noncurrent | 171.7 |
Operating Lease |  |
Lease Maturity [Line Items] |  |
Operating Leases, Future Minimum Payments Due, Next Twelve Months | 11.7 |
Operating Leases, Future Minimum Payments, Due in Two Years | 5.2 |
Operating Leases, Future Minimum Payments, Due in Three Years | 4.7 |
Operating Leases, Future Minimum Payments, Due in Four Years | 4.5 |
Operating Leases, Future Minimum Payments, Due in Five Years | 3.7 |
Operating Leases, Future Minimum Payments, Due Thereafter | 18.2 |
Lessee, Operating Lease, Liability, Payments, Due | 48.0 |
Lessee, Operating Lease, Liability, Undiscounted Excess Amount | (7.8) |
Operating Lease, Liability | 40.2 |
Operating Lease, Liability, Current | 10.3 |
Operating Lease, Liability, Noncurrent | $ 29.9 |

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