Financial Guaranty Variable Interest Entities and Consolidated Investment Vehicles - Contractual Maturity (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Estimated Fair Value
Total	$ 7,119	$ 8,202
Variable Interest Entity, Primary Beneficiary \| Financial Guaranty Variable Interest Entities \| Puerto Rico Trusts
Amortized Cost
Due within one year	1
Due after one year through five years	6
Due after five years through 10 years	41
Due after 10 years	156
Total	204
Estimated Fair Value
Due within one year	1
Due after one year through five years	5
Due after five years through 10 years	41
Due after 10 years	157
Total	$ 204

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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