Asset Retirement Obligations - MEC - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Asset Retirement Obligations By Type [Line Items]
Regulatory liabilities	$ 7,033	$ 6,818
Cost of removal
Asset Retirement Obligations By Type [Line Items]
Regulatory liabilities	2,918	2,741
Cost of removal | MEC
Asset Retirement Obligations By Type [Line Items]
Regulatory liabilities	$ 452	$ 411