Regulatory Matters - EEGH - Regulatory Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Sep. 01, 2023
Regulatory Liabilities [Line Items]
Total regulatory liabilities	$ 7,033	$ 6,818
Regulatory liabilities, noncurrent	6,754	6,644
Deferred income taxes
Regulatory Liabilities [Line Items]
Total regulatory liabilities	2,493	2,733	$ 24
Other postretirement benefit costs
Regulatory Liabilities [Line Items]
Total regulatory liabilities	$ 292	211
Cost of removal
Regulatory Liabilities [Line Items]
Regulatory liability, amortization period	27 years
Total regulatory liabilities	$ 2,918	2,741
EEGH
Regulatory Liabilities [Line Items]
Total regulatory liabilities	656	656
Regulatory liabilities, current	29	33
Regulatory liabilities, noncurrent	627	623
EEGH | Deferred income taxes
Regulatory Liabilities [Line Items]
Total regulatory liabilities	416	425	$ 24
EEGH | Other postretirement benefit costs
Regulatory Liabilities [Line Items]
Total regulatory liabilities	$ 129	124
EEGH | Cost of removal
Regulatory Liabilities [Line Items]
Regulatory liability, amortization period	48 years
Total regulatory liabilities	$ 92	85
Regulatory liabilities, noncurrent	92	85
EEGH | Other
Regulatory Liabilities [Line Items]
Total regulatory liabilities	$ 19	$ 22