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Other Commitments And Contingencies Other Commitments and Contingencies (Contractual Obligation, Fiscal Year Maturity Schedule) (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Long-term Purchase Commitment [Line Items] |  |  |
Long-term Debt, Future Minimum Payments Due | [1] | $ 7,029.6 |
Long-term Debt, Future Minimum Payments Due, Next Twelve Months | [1] | 41.0 |
Long-term Debt, Future Minimum Payments, Due in Two Years | [1] | 0.0 |
Long-term Debt, Future Minimum Payments, Due in Three Years | [1] | 63.6 |
Long-term Debt, Future Minimum Payments, Due in Four Years | [1] | 530.0 |
Long-term Debt, Future Minimum Payments, Due in Five Years | [1] | 600.0 |
Long-term Debt, Future Minimum Payments, Due Thereafter | [1] | 5,795.0 |
Capital Leases, Future Minimum Payments Due | [2] | 322.4 |
Capital Leases, Future Minimum Payments Due, Next Twelve Months | [2] | 23.0 |
Capital Leases, Future Minimum Payments Due in Two Years | [2] | 22.5 |
Capital Leases, Future Minimum Payments Due in Three Years | [2] | 22.6 |
Capital Leases, Future Minimum Payments Due in Four Years | [2] | 22.1 |
Capital Leases, Future Minimum Payments Due in Five Years | [2] | 19.8 |
Capital Leases, Future Minimum Payments Due Thereafter | [2] | 212.4 |
Interest Payments on Long-term Debt, Future Minimum Payments Due |  | 6,311.7 |
Interest Payments on Long-term Debt, Future Minimum Payments Due, Next Twelve Months |  | 319.8 |
Interest Payments on Long-term Debt, Future Minimum Payments, Due in Two Years |  | 318.6 |
Interest Payments on Long-term Debt, Future Minimum Payments, Due in Three Years |  | 318.6 |
Interest Payments on Long-term Debt, Future Minimum Payments, Due in Four Years |  | 315.0 |
Interest Payments on Long-term Debt, Future Minimum Payments, Due in Five Years |  | 289.0 |
Interest Payments on Long-term Debt, Future Minimum Payments, Due Thereafter |  | 4,750.7 |
Operating Leases, Future Minimum Payments Due | [3] | 45.9 |
Operating Leases, Future Minimum Payments Due, Next Twelve Months | [3] | 11.0 |
Operating Leases, Future Minimum Payments, Due in Two Years | [3] | 7.3 |
Operating Leases, Future Minimum Payments, Due in Three Years | [3] | 6.1 |
Operating Leases, Future Minimum Payments, Due in Four Years | [3] | 4.2 |
Operating Leases, Future Minimum Payments, Due in Five Years | [3] | 2.8 |
Operating Leases, Future Minimum Payments, Due Thereafter | [3] | 14.5 |
Energy Commodity Contracts, Future Minimum Payments Due |  | 154.3 |
Energy Commodity Contracts, Future Minimum Payments Due, Next Twelve Months |  | 99.2 |
Energy Commodity Contracts, Future Minimum Payments, Due in Two Years |  | 55.1 |
Energy Commodity Contracts, Future Minimum Payments, Due in Three Years |  | 0.0 |
Energy Commodity Contracts, Future Minimum Payments, Due in Four Years |  | 0.0 |
Energy Commodity Contracts, Future Minimum Payments, Due in Five Years |  | 0.0 |
Energy Commodity Contracts, Future Minimum Payments, Due Thereafter |  | 0.0 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments Due |  | 3,566.7 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments Due, Next Twelve Months |  | 592.3 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due in Two Years |  | 487.7 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due in Three Years |  | 450.5 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due in Four Years |  | 437.5 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due in Five Years |  | 260.8 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due Thereafter |  | 1,337.9 |
Service Obligations, IBM Service Obligations, Future Minimum Payments Due |  | 211.0 |
Service Obligations, IBM Service Obligations, Future Minimum Payments Due, Next Twelve Months |  | 68.3 |
Service Obligations, IBM Service Obligations, Future Minimum Payments, Due in Two Years |  | 60.0 |
Service Obligations, IBM Service Obligations, Future Minimum Payments, Due in Three Years |  | 47.1 |
Service Obligations, IBM Service Obligations, Future Minimum Payments, Due in Four Years |  | 35.6 |
Service Obligations, IBM Service Obligations, Future Minimum Payments, Due in Five Years |  | 0.0 |
Service Obligations, IBM Service Obligations, Future Minimum Payments, Due Thereafter |  | 0.0 |
Service Obligations, Other Service Obligations, Future Minimum Payments Due |  | 86.7 |
Service Obligations, Other Service Obligations, Future Minimum Payments Due, Next Twelve Months |  | 33.5 |
Service Obligations, Other Service Obligations, Future Minimum Payments, Due in Two Years |  | 43.6 |
Service Obligations, Other Service Obligations, Future Minimum Payments, Due in Three Years |  | 9.6 |
Service Obligations, Other Service Obligations, Future Minimum Payments, Due in Four Years |  | 0.0 |
Service Obligations, Other Service Obligations, Future Minimum Payments, Due in Five Years |  | 0.0 |
Service Obligations, Other Service Obligations, Future Minimum Payments, Due Thereafter |  | 0.0 |
Other Liabilities, Future Minimum Payments Due |  | 24.2 |
Other Liabilities, Future Minimum Payments Due, Next Twelve Months |  | 24.2 |
Other Liabilities, Future Minimum Payments, Due in Two Years |  | 0.0 |
Other Liabilities, Future Minimum Payments, Due in Three Years |  | 0.0 |
Other Liabilities, Future Minimum Payments, Due in Four Years |  | 0.0 |
Other Liabilities, Future Minimum Payments, Due in Five Years |  | 0.0 |
Other Liabilities, Future Minimum Payments, Due Thereafter |  | 0.0 |
Total Future Minimum Lease Payments Due |  | 17,752.5 |
Total Future Minimum Lease Payments Due, Next Twelve Months |  | 1,212.3 |
Total Future Minimum Lease Payments, Due in Two Years |  | 994.8 |
Total Future Minimum Lease Payments, Due in Three Years |  | 918.1 |
Total Future Minimum Lease Payments, Due in Four Years |  | 1,344.4 |
Total Future Minimum Lease Payments, Due in Five Years |  | 1,172.4 |
Total Future Minimum Lease Payments, Due Thereafter |  | 12,110.5 |
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net |  | (68.5) | $ (71.5)
Capital Leases, Future Minimum Payments, Interest Included in Payments |  | 114.6 |
Accrual for Environmental Loss Contingencies |  | 101.2 | $ 111.4
Fleet Lease |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
Operating Leases, Future Minimum Payments Due, Next Twelve Months |  | 26.7 |
Operating Leases, Future Minimum Payments, Due in Two Years |  | 22.4 |
Operating Leases, Future Minimum Payments, Due in Three Years |  | 16.6 |
Operating Leases, Future Minimum Payments, Due in Four Years |  | 12.3 |
Operating Leases, Future Minimum Payments, Due in Five Years |  | 9.3 |
Operating Leases, Future Minimum Payments, Due Thereafter |  | $ 8.8 |
[1] | Long-term debt balance excludes unamortized issuance costs and discounts of $68.5 million.
[2] | Capital lease payments shown above are inclusive of interest totaling $114.6 million.
[3] | Operating lease balances do not include amounts for fleet leases that can be renewed beyond the initial lease term. The Company anticipates renewing the leases beyond the initial term, but the anticipated payments associated with the renewals do not meet the definition of expected minimum lease payments and therefore are not included above. Expected payments are $26.7 million in 2019, $22.4 million in 2020, $16.6 million in 2021, $12.3 million in 2022, $9.3 million in 2023 and $8.8 million thereafter.

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