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	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Redeemable Noncontrolling Interest, Equity, Other, Fair Value, Rollforward [Roll Forward]
Contributions	$ 35	$ 6	$ 40	$ 9
Distributions	(7)	(3)	(15)	(9)
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	21	0	21	0
Distributions	(21)	0	(21)	0
Ending balance	$ 21	$ 21	$ 21	$ 21

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

No definition available.

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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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-Publisher FASB
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-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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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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