Insurance Company Regulatory Requirements - Insurance Regulatory Amounts Reported (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Assured Guaranty Municipal Corp
Statutory Accounting Practices [Line Items]
Policyholders’ Surplus	$ 2,747	$ 3,053
Net Income (Loss)	163	352	$ 398
Statutory capital and surplus required	855	877
AGC
Statutory Accounting Practices [Line Items]
Policyholders’ Surplus	1,916	2,070
Net Income (Loss)	62	282	73
Statutory capital and surplus required	347	348
AG Re
Statutory Accounting Practices [Line Items]
Policyholders’ Surplus	839	944
Net Income (Loss)	53	121	24
AGRO
Statutory Accounting Practices [Line Items]
Policyholders’ Surplus	390	425
Net Income (Loss)	$ 9	$ 6	$ 7

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529

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- Definition

Amount of statutory capital required to be maintained as of the balance sheet date under prescribed or permitted statutory accounting practices.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529

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- Definition

Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators.

+ References

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