Recent Financing Transactions - MEC (Details) - First Mortgage Bonds, 5.30%, due 2055 - MEC - Subsidiary Debt $ in Millions	1 Months Ended
Jan. 31, 2024 USD ($)
Debt Instrument [Line Items]
Face amount	$ 600
Stated interest rate	5.30%
Proceeds allocation period	24 months

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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+ Details