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Other Commitments and Contingencies (Contractual Obligation, Fiscal Year Maturity Schedule) (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Long-term Purchase Commitment [Line Items] |  |
Long-term Debt, Future Minimum Payments Due | $ 13,205.0 |
Long-term Debt, Future Minimum Payments Due, Next Twelve Months | 1,260.0 |
Long-term Debt, Future Minimum Payments, Due in Two Years | 0.0 |
Long-term Debt, Future Minimum Payments, Due in Three Years | 1,090.0 |
Long-term Debt, Future Minimum Payments, Due in Four Years | 1,055.0 |
Long-term Debt, Future Minimum Payments, Due in Five Years | 1,350.0 |
Long-term Debt, Future Minimum Payments, Due Thereafter | 8,450.0 |
Interest Payments on Long-term Debt, Future Minimum Payments Due | 8,090.3 |
Interest Payments on Long-term Debt, Future Minimum Payments Due, Next Twelve Months | 566.2 |
Interest Payments on Long-term Debt, Future Minimum Payments, Due in Two Years | 551.1 |
Interest Payments on Long-term Debt, Future Minimum Payments, Due in Three Years | 531.7 |
Interest Payments on Long-term Debt, Future Minimum Payments, Due in Four Years | 481.6 |
Interest Payments on Long-term Debt, Future Minimum Payments, Due in Five Years | 453.9 |
Interest Payments on Long-term Debt, Future Minimum Payments, Due Thereafter | 5,505.8 |
Finance Leases, Future Minimum Payments Due | 429.4 |
Finance Leases, Future Minimum Payments Due, Next Twelve Months | 34.6 |
Finance Leases, Future Minimum Payments Due in Two Years | 29.4 |
Finance Leases, Future Minimum Payments Due in Three Years | 24.2 |
Finance Leases, Future Minimum Payments Due in Four Years | 23.0 |
Finance Leases, Future Minimum Payments Due in Five Years | 19.0 |
Finance Leases, Future Minimum Payments Due Thereafter | 299.2 |
Operating Leases, Future Minimum Payments Due | 30.9 |
Operating Leases, Future Minimum Payments Due, Next Twelve Months | 10.0 |
Operating Leases, Future Minimum Payments, Due in Two Years | 5.3 |
Operating Leases, Future Minimum Payments, Due in Three Years | 4.3 |
Operating Leases, Future Minimum Payments, Due in Four Years | 3.1 |
Operating Leases, Future Minimum Payments, Due in Five Years | 2.5 |
Operating Leases, Future Minimum Payments, Due Thereafter | 5.7 |
Energy Commodity Contracts, Future Minimum Payments Due | 119.7 |
Energy Commodity Contracts, Future Minimum Payments Due, Next Twelve Months | 118.5 |
Energy Commodity Contracts, Future Minimum Payments, Due in Two Years | 0.3 |
Energy Commodity Contracts, Future Minimum Payments, Due in Three Years | 0.3 |
Energy Commodity Contracts, Future Minimum Payments, Due in Four Years | 0.4 |
Energy Commodity Contracts, Future Minimum Payments, Due in Five Years | 0.2 |
Energy Commodity Contracts, Future Minimum Payments, Due Thereafter | 0.0 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments Due | 2,694.6 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments Due, Next Twelve Months | 685.5 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due in Two Years | 631.2 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due in Three Years | 609.2 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due in Four Years | 373.2 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due in Five Years | 245.2 |
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due Thereafter | 150.3 |
Service Obligations, IT Service Obligations, Future Minimum Payments Due | 120.7 |
Service Obligations, IT Service Obligations, Future Minimum Payments Due, Next Twelve Months | 73.9 |
Service Obligations, IT Service Obligations, Future Minimum Payments, Due in Two Years | 30.3 |
Service Obligations, IT Service Obligations, Future Minimum Payments, Due in Three Years | 11.4 |
Service Obligations, IT Service Obligations, Future Minimum Payments, Due in Four Years | 5.1 |
Service Obligations, IT Service Obligations, Future Minimum Payments, Due in Five Years | 0.0 |
Service Obligations, IT Service Obligations, Future Minimum Payments, Due Thereafter | 0.0 |
Plant equipment purchase obligations, Future Minimum Payments, Due Thereafter | 0.0 |
Plant equipment purchase obligations, Future Minimum Payments, Due in Five Years | 0.0 |
Plant equipment purchase obligations, Future Minimum Payments, Due in Four Years | 3.8 |
Plant equipment purchase obligations, Future Minimum Payments, Due in Three Years | 4.3 |
Plant equipment purchase obligations, Future Minimum Payments, Due in Two Years | 24.9 |
Plant equipment purchase obligations, Future Minimum Payments Due, Next Twelve Months | 140.5 |
Plant equipment purchase obligations, Future Minimum Payments Due | 173.5 |
Other Liabilities, Future Minimum Payments Due | 336.0 |
Other Liabilities, Future Minimum Payments Due, Next Twelve Months | 287.0 |
Other Liabilities, Future Minimum Payments, Due in Two Years | 7.9 |
Other Liabilities, Future Minimum Payments, Due in Three Years | 7.7 |
Other Liabilities, Future Minimum Payments, Due in Four Years | 7.6 |
Other Liabilities, Future Minimum Payments, Due in Five Years | 7.7 |
Other Liabilities, Future Minimum Payments, Due Thereafter | 18.1 |
Total Future Contractual Obligations Due | 25,200.1 |
Total Future Contractual Obligations Due, Next Twelve Months | 3,176.2 |
Total Future Contractual Obligations, Due in Two Years | 1,280.4 |
Total Future Contractual Obligations, Due in Three Years | 2,283.1 |
Total Future Contractual Obligations, Due in Four Years | 1,952.8 |
Total Future Contractual Obligations, Due in Five Years | 2,078.5 |
Total Future Contractual Obligations, Due Thereafter | 14,429.1 |
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net | (95.5) | $ (81.1)
Finance Lease, Liability, Undiscounted Excess Amount | (183.2) |
Lessee, Operating Lease, Liability, Undiscounted Excess Amount | $ (3.6) |

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