Leases - Summary of Lease Assets and Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Schedule Of Assets And Liabilities Lessee [Line Items]
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets Noncurrent	Other Assets Noncurrent
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other Liabilities Current	Other Liabilities Current
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Deferred Credits And Other Liabilities Noncurrent	Deferred Credits And Other Liabilities Noncurrent
Total lease liabilities	$ 25	$ 27
Other Deferred Debits [Member]
Schedule Of Assets And Liabilities Lessee [Line Items]
Right-of-use asset	24	26
Other Current Liabilities [Member]
Schedule Of Assets And Liabilities Lessee [Line Items]
Current	2	2
Deferred Credits and Other Liabilities [Member]
Schedule Of Assets And Liabilities Lessee [Line Items]
Long-term	$ 23	$ 25