Derivatives and Risk Management Activities - Net Unrealized Gain/(Loss) Recognized in AOCI (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Derivative assets and liabilities
Settlement of terminated interest rate hedging instruments (Note 7)			$ 80
Other current assets
Derivative assets and liabilities
Net fair value of interest rate hedges	$ 47		47		$ 75
Other long-term liabilities and deferred credits
Derivative assets and liabilities
Net fair value of interest rate hedges	(5)		(5)
Other long-term assets, net
Derivative assets and liabilities
Net fair value of interest rate hedges					$ 45
AOCI cash flow hedge
Derivative assets and liabilities
Net gain/(loss) deferred in AOCI	(100)		(100)
Interest rate swap terminated | Cash flow hedge
Derivative assets and liabilities
Notional amount	200		200
Settlement of terminated interest rate hedging instruments (Note 7)	80
Interest rate swap terminated | Cash flow hedge | AOCI cash flow hedge
Derivative assets and liabilities
Net gain/(loss) deferred in AOCI	73		73
Interest rate derivatives
Derivative assets and liabilities
Interest rate derivatives, net	$ 8	$ 36	$ 2	$ 68