Risk Management and Hedging Activities - PAC - Balance Sheet Location (Details) - PAC - Commodity derivatives - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	$ (97)	$ (76)
Cash collateral receivable (payable)	6	10
Total derivatives - net basis	(91)	(66)
Other current assets
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	9	18
Cash collateral receivable (payable)	0	(2)
Total derivatives - net basis	9	16
Other non-current assets
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	0	2
Cash collateral receivable (payable)	0	0
Total derivatives - net basis	0	2
Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	(89)	(76)
Cash collateral receivable (payable)	6	12
Total derivatives - net basis	(83)	(64)
Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	(17)	(20)
Cash collateral receivable (payable)	0	0
Total derivatives - net basis	(17)	(20)
Not designated as hedging contracts
Derivatives, Fair Value [Line Items]
Derivative asset, not subject to master netting arrangement	27	32
Derivative liability, not subject to master netting arrangement	(124)	(108)
Derivative, fair value, net	(97)	(76)
Net regulatory asset (liability) on derivative contracts	97	76	$ (270)	$ (53)
Not designated as hedging contracts | Other current assets
Derivatives, Fair Value [Line Items]
Derivative asset, not subject to master netting arrangement	10	21
Derivative liability, not subject to master netting arrangement	(1)	(3)
Derivative, fair value, net	9	18
Not designated as hedging contracts | Other non-current assets
Derivatives, Fair Value [Line Items]
Derivative asset, not subject to master netting arrangement	0	2
Derivative liability, not subject to master netting arrangement	0	0
Derivative, fair value, net	0	2
Not designated as hedging contracts | Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative asset, not subject to master netting arrangement	16	7
Derivative liability, not subject to master netting arrangement	(105)	(83)
Derivative, fair value, net	(89)	(76)
Not designated as hedging contracts | Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative asset, not subject to master netting arrangement	1	2
Derivative liability, not subject to master netting arrangement	(18)	(22)
Derivative, fair value, net	$ (17)	$ (20)