Financial Risk Management Activities - Gross & Net Fair Values of Financial Risk Management Derivative Instruments (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Assets - Gross fair value of derivative contracts	$ 0	$ 0
Liabilities - Gross fair value of derivative contracts	(8)	(6)
Gross amount offset in the Consolidate Balance Sheet, Assets	0	0
Gross amount offset in the Consolidate Balance Sheet, Liabilities	0	0
Derivative Asset	0	0
Derivative Liability	$ (8)	$ (6)
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Derivative Contracts Designated as Hedging Instruments:
Derivatives, Fair Value [Line Items]
Assets - Gross fair value of derivative contracts	$ 0	$ 0
Liabilities - Gross fair value of derivative contracts	(2)	(4)
Derivative Contracts Designated as Hedging Instruments: | Interest Rate Swaps
Derivatives, Fair Value [Line Items]
Assets - Gross fair value of derivative contracts	0	0
Liabilities - Gross fair value of derivative contracts	(2)	(4)
Derivative Contracts Not Designated as Hedging Instruments:
Derivatives, Fair Value [Line Items]
Assets - Gross fair value of derivative contracts	0	0
Liabilities - Gross fair value of derivative contracts	(6)	(2)
Derivative Contracts Not Designated as Hedging Instruments: | Foreign Exchange Forwards / Swaps
Derivatives, Fair Value [Line Items]
Assets - Gross fair value of derivative contracts	0	0
Liabilities - Gross fair value of derivative contracts	$ (6)	$ (2)