Financial Guaranty Variable Interest Entities and Consolidated Investment Vehicles - Schedule of Redeemable Noncontrolling Interest of Consolidated Investment Vehicle (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Redeemable Noncontrolling Interest, Equity, Other, Fair Value, Rollforward [Roll Forward]
Contributions	$ 23	$ 25	$ 63	$ 34
Distributions	(36)	(2)	(51)	(11)
Consolidated Investment Vehicles
Redeemable Noncontrolling Interest, Equity, Other, Fair Value, Rollforward [Roll Forward]
Beginning balance	21	21	22	21
Net income (loss) attributable to the redeemable noncontrolling interest	0	0	(1)	0
Contributions	0	0	21	0
Distributions	0	0	(21)	0
Ending balance	$ 21	$ 21	$ 21	$ 21

Redeemable Noncontrolling Interest, Equity, Other, Fair Value, Rollforward [Roll Forward]

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- Definition

Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

+ References

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- Definition

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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- Definition

Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

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- Definition

Fair value of noncontrolling interests which are redeemable by the parent entity and classified as other equity.

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