Financial Guarantees in Force - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Guarantor Obligations [Line Items]
Financial Guarantee Insurance Contracts, Accelerated Premium Revenue, Amount	$ 0	$ 8	$ 1
Gross par amount of financial guarantees outstanding	26,005	27,551
Net par amount of financial guarantees	19,541	22,613
Gross financial guarantees in force	41,733	44,734
Net financial guarantees in force	$ 29,121	34,975
Ceded Principal Outstanding Major Reinsurer Percentage	10.60%
Public Finance [Member]
Guarantor Obligations [Line Items]
Net par amount of financial guarantees	$ 7,562	$ 10,547