Insurance Company Regulatory Requirements - Insurance Regulatory Amounts Reported (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Assured Guaranty Municipal Corp
Statutory Accounting Practices [Line Items]
Policyholders’ Surplus	$ 2,646	$ 2,747
Net Income (Loss)	209	163	$ 352
Statutory capital and surplus required	876	855
AGC
Statutory Accounting Practices [Line Items]
Policyholders’ Surplus	1,651	1,916
Net Income (Loss)	79	62	282
Statutory capital and surplus required	420	347
AG Re
Statutory Accounting Practices [Line Items]
Policyholders’ Surplus	905	839
Net Income (Loss)	95	53	121
AGRO
Statutory Accounting Practices [Line Items]
Policyholders’ Surplus	412	390
Net Income (Loss)	$ 16	$ 9	$ 6