Pension and Other Postretirement Employee Benefits (OPEB) Plans - Schedule of Health Care Cost Trend Rates (Details) - OPEB costs	Dec. 31, 2024	Dec. 31, 2023
Assumed Health Care Cost Trend Rates-Not Medicare Eligible:
Assumed Health Care Cost Trend Rates [Abstract]
Health care cost trend rate assumed for next year	7.00%	7.00%
Rate to which the cost trend is expected to decline (the ultimate trend rate)	4.50%	4.50%
Health care cost trend rate assumed for next year (Vistra Plan)
Assumed Health Care Cost Trend Rates [Abstract]
Health care cost trend rate assumed for next year	15.70%	12.90%
Health care cost trend rate assumed for next year (Split-Participant Plan)
Assumed Health Care Cost Trend Rates [Abstract]
Health care cost trend rate assumed for next year	13.80%	12.30%
Rate to which the cost trend is expected to decline (the ultimate trend rate)
Assumed Health Care Cost Trend Rates [Abstract]
Rate to which the cost trend is expected to decline (the ultimate trend rate)	4.50%	4.50%