Income Taxes - PAC - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Deferred income tax assets:
Regulatory liabilities	$ 1,248	$ 1,323
Loss contingencies	431	109
AROs	318	283
Other	629	632
Total deferred income tax assets	3,400	3,159
Valuation allowances	(142)	(187)
Total deferred income tax assets, net	3,258	2,972
Deferred income tax liabilities:
Property-related items	(12,596)	(12,244)
Regulatory assets	(1,034)	(898)
Other	(491)	(510)
Total deferred income tax liabilities	(15,695)	(15,650)
Net deferred income tax liability	(12,437)	(12,678)
PAC
Deferred income tax assets:
Regulatory liabilities	643	724
Employee benefits	51	59
State carryforwards	84	73
Loss contingencies	429	107
AROs	85	79
Other	117	80
Total deferred income tax assets	1,409	1,122
Valuation allowances	(24)	(35)
Total deferred income tax assets, net	1,385	1,087
Deferred income tax liabilities:
Property-related items	(3,704)	(3,612)
Regulatory assets	(632)	(462)
Other	(134)	(165)
Total deferred income tax liabilities	(4,470)	(4,239)
Net deferred income tax liability	$ (3,085)	$ (3,152)