Borrowings and Other Financing Instruments - Long-Term Borrowings (Details) - Series Due June 1, 2054 - Bonds [Member] $ in Millions	Sep. 30, 2024 USD ($)
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.00%
Debt Instrument, Face Amount	$ 600

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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