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Winter Storm Uri (Details) - USD ($) |  | 1 Months Ended | 4 Months Ended |  |
--- | --- | --- | --- | --- | ---
Oct. 25, 2022 | Feb. 28, 2021 | Dec. 31, 2022 | Sep. 30, 2022 | Mar. 31, 2021
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Aggregate natural gas purchases |  | $ 2,300,000,000 |  |  |
Regulatory assets |  |  | $ 2,471,810,000 | $ 2,605,372,000 |
Winter Storm Uri incremental costs |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Regulatory assets |  |  | 2,125,787,000 | $ 2,109,454,000 |
Winter Storm Uri incremental costs | Winter Storm Uri |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Regulatory assets |  |  | 2,100,000,000 |  |
Winter Storm Uri incremental costs | Winter Storm Uri | Kansas |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Regulatory assets |  |  | 89,000,000 |  |
Winter Storm Uri incremental costs | Winter Storm Uri | Texas |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Regulatory assets |  |  | 2,021,900,000 |  |
Regulatory asset, deferred costs |  |  | $ 14,900,000 |  |
Extraordinary Gas Cost | Winter Storm Uri | Kansas |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Regulatory asset, authorized | $ 118,500,000 |  |  |  |
Regulatory asset, amortization period | 12 years |  |  |  |
Senior Notes Due 2023 |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Debt instrument, face amount |  |  |  |  | $ 2,200,000,000

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