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Commitments and Contingencies Commitments and Contingencies - Table (Details) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2016 USD ($)
Obligations |  |
Time period shown for contractual commitments | 5 years |
Membership interest of variable interest entity subject to mandatory redemption |  |
Obligations |  |
2017 | $ 2 |
2018 | 2 |
2019 | 2 |
2020 | 3 |
2021 | 3 |
Thereafter | 23 |
Total | 35 |
Lease Obligations - Capital |  |
Obligations |  |
2017 | 51 | [1]
2018 | 51 | [1]
2019 | 50 | [1]
2020 | 50 | [1]
2021 | 50 | [1]
Thereafter | 564 | [1]
Total | 816 | [1]
Lease Obligations - Non-Cancelable Operating |  |
Obligations |  |
2017 | 43 | [2]
2018 | 32 | [2]
2019 | 25 | [2]
2020 | 25 | [2]
2021 | 25 | [2]
Thereafter | 13 | [2]
Total | 163 | [2]
Purchase Obligations - Power |  |
Obligations |  |
2017 | 254 | [3]
2018 | 265 | [3]
2019 | 266 | [3]
2020 | 246 | [3]
2021 | 244 | [3]
Thereafter | 1,541 | [3]
Total | 2,816 | [3]
Purchase Obligations - Fuel |  |
Obligations |  |
2017 | 1,312 | [4]
2018 | 917 | [4]
2019 | 569 | [4]
2020 | 324 | [4]
2021 | 327 | [4]
Thereafter | 1,006 | [4]
Total | 4,455 | [4]
Purchase Obligations - Other |  |
Obligations |  |
2017 | 88 | [5]
2018 | 65 | [5]
2019 | 58 | [5]
2020 | 47 | [5]
2021 | 34 | [5]
Thereafter | 604 | [5]
Total | 896 | [5]
Unfunded Loan Commitment |  |
Obligations |  |
2017 | 9 |
2018 | 4 |
Total | 13 |
Payments on Other Financings |  |
Obligations |  |
2017 | 76 |
2018 | 76 |
2019 | 75 |
2020 | 73 |
2021 | 207 |
Thereafter | 26 |
Total | 533 |
Total |  |
Obligations |  |
2017 | 1,835 |
2018 | 1,412 |
2019 | 1,045 |
2020 | 768 |
2021 | 890 |
Thereafter | 3,777 |
Total | $ 9,727 |
[1] | (1) Includes the interest component of capital leases based on the interest rates stated in the lease agreements and excludes certain related executory costs. Minimum commitments related to executory costs are included in purchase obligations.
[2] | (2) Does not include purchased power agreements that are accounted for as operating leases and included in power purchase obligations.
[3] | (3) Includes commitments for energy and/or capacity under power purchase agreements from coal-fired, hydroelectric, diesel, and gas-fired facilities, as well as transmission service agreements to support purchases of power from the market and wind power purchase agreements.
[4] | (4) Includes commitments to purchase nuclear fuel, coal, and natural gas, as well as related transportation and storage services.
[5] | (5) Primarily includes long-term service contracts, contracts that contain minimum purchase levels for the purchase of limestone along with related storage and transportation, and contractual obligations related to load control programs.

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