Insurance In Force (Summary Of Company's Reinsurance Agreements For U.S. Public Finance And Structured Finance And International Insurance Operations) (Detail) - USD ($) $ in Millions		Dec. 31, 2022	Dec. 31, 2021
Ceded Par Outstanding		$ 897	$ 1,000
Letters of Credit/Trust Accounts		18
Reinsurance Recoverable/ (Payable)	[1]	9
Assured Guaranty Corp [Member]
Ceded Par Outstanding		372
Letters of Credit/Trust Accounts		0
Reinsurance Recoverable/ (Payable)	[1]	3
Assured Guaranty Re Ltd [Member]
Ceded Par Outstanding	[2]	475
Letters of Credit/Trust Accounts	[2]	18
Reinsurance Recoverable/ (Payable)	[1],[2]	6
Others [Member]
Ceded Par Outstanding	[2]	50
Letters of Credit/Trust Accounts	[2]	0
Reinsurance Recoverable/ (Payable)	[1],[2]	$ 0

[1] Total reinsurance recoverable/(payable) is primarily related to recoverables on paid and unpaid losses net of paid and unpaid salvage due to reinsurers.

[2] Represents a withdrawal of ratings.