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Commitment, Contingencies And Guarantees: Purchase Commitment (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2021 USD ($) MMBTU | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Long-term Purchase Commitment [Line Items] |  |  |
2021 | 12,588,974 |  |
2022 | 12,012,500 |  |
2023 | 8,220,000 |  |
2024 | 4,560,000 |  |
2025 | 0 |  |
Thereafter | 0 |  |
Natural Gas, Distribution |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
Natural Gas Purchases | $ | $ 61 | $ 25 | $ 7
El Paso - Bondad Station |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
2021 | 31,000 |  |
2022 | 0 |  |
2023 | 0 |  |
2024 | 0 |  |
2025 | 0 |  |
Thereafter | 0 |  |
Kern River - Opal |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
2021 | 9,300 |  |
2022 | 0 |  |
2023 | 0 |  |
2024 | 0 |  |
2025 | 0 |  |
Thereafter | 0 |  |
El Paso - San Juan Basin |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
2021 | 182,550 |  |
2022 | 0 |  |
2023 | 0 |  |
2024 | 0 |  |
2025 | 0 |  |
Thereafter | 0 |  |
Enable East Pipeline |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
2021 | 1,825,000 |  |
2022 | 450,000 |  |
2023 | 0 |  |
2024 | 0 |  |
2025 | 0 |  |
Thereafter | 0 |  |
Northern Natural Gas - Demarc |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
2021 | 1,614 |  |
2022 | 0 |  |
2023 | 0 |  |
2024 | 0 |  |
2025 | 0 |  |
Thereafter | 0 |  |
Northern Natural Gas - Ventura |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
2021 | 1,810,000 |  |
2022 | 1,840,000 |  |
2023 | 1,820,000 |  |
2024 | 0 |  |
2025 | 0 |  |
Thereafter | 0 |  |
Northwest Pipeline - Wyoming |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
2021 | 1,531,700 |  |
2022 | 1,510,000 |  |
2023 | 910,000 |  |
2024 | 0 |  |
2025 | 0 |  |
Thereafter | 0 |  |
ONEOK - Oklahoma |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
2021 | 5,475,000 |  |
2022 | 5,475,000 |  |
2023 | 5,490,000 |  |
2024 | 4,560,000 |  |
2025 | 0 |  |
Thereafter | 0 |  |
Southern Star Central Gas Pipeline |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
2021 | 113,130 |  |
2022 | 0 |  |
2023 | 0 |  |
2024 | 0 |  |
2025 | 0 |  |
Thereafter | 0 |  |
Panhandle Eastern Pipe Line |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
2021 | 1,609,680 |  |
2022 | 2,737,500 |  |
2023 | 0 |  |
2024 | 0 |  |
2025 | 0 |  |
Thereafter | 0 |  |
Gas Utilities |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
Term of Evergreen Contracts | 60 days |  |
Maximum |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
We maintain natural gas supply contracts with several vendors that generally cover a period up to: | 1 year |  |

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