Significant Accounting Policies (Reconciliation of Total Cash, Restricted Cash and Equivalents) (Parenthetical) (Detail) - USD ($) $ in Millions		Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash Cash Equivalents And Restricted Cash [Line Items]
Cash and cash equivalents	[1]	$ 310	$ 184
Restricted cash and equivalents			$ 4	$ 2	$ 3
Restricted Cash and Cash Equivalents, Current, Statement of Financial Position [Extensible Enumeration]			Disposal Group, Including Discontinued Operation, Assets, Current	Disposal Group, Including Discontinued Operation, Assets, Current	Disposal Group, Including Discontinued Operation, Assets, Current
VIE
Cash Cash Equivalents And Restricted Cash [Line Items]
Restricted cash and equivalents		$ 41
Assets Held For Sale
Cash Cash Equivalents And Restricted Cash [Line Items]
Cash and cash equivalents			$ 33	$ 34	$ 49

[1] See Note 16 for amounts attributable to VIEs.