Outstanding Exposure - Amortization Schedule of Puerto Rico Net Par Outstanding and Net Debt Service Outstanding (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Scheduled Net Par Amortization
Total	$ 236,383	$ 233,258
Scheduled Net Debt Service Amortization
Total	374,475	369,951
Puerto Rico
Scheduled Net Par Amortization
2023 (April 1 - June 30)	0
2023 (July 1 - September 30)	124
2023 (October 1 - December 31)	0
Subtotal 2023	124
2024	110
2025	94
2026	149
2027	124
2028-2032	378
2033-2037	240
2038-2041	132
Total	1,351	$ 1,361
Scheduled Net Debt Service Amortization
2023 (April 1 - June 30)	3
2023 (July 1 - September 30)	154
2023 (October 1 - December 31)	3
Subtotal 2023	160
2024	170
2025	148
2026	200
2027	168
2028-2032	528
2033-2037	311
2038-2041	150
Total	$ 1,835

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Represents the amount of insured contractual payments (principal and interest) outstanding on the underlying insured obligations for financial guaranty contracts, net of ceded contracts.

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Insured Financial Obligations, Maturities of Outstanding Contractual Payments, Remainder Of Fiscal Year

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Insured Financial Obligations, Maturities of Outstanding Contractual Payments, Year Fifteen to Eighteen

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Insured Financial Obligations, Maturities of Outstanding Contractual Payments, Year Five To Nine

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Insured Financial Obligations, Maturities of Outstanding Contractual Payments, Year One

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Insured Financial Obligations, Maturities of Outstanding Contractual Payments, Year Ten to Fourteen

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Insured Financial Obligations, Maturities of Outstanding Principal Amount, Remainder Of Fiscal Year

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Insured Financial Obligations, Maturities of Outstanding Principal Amount, Year Fifteen to Eighteen

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Insured Financial Obligations, Maturities of Outstanding Principal Amount, Year Five To Nine

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Insured Financial Obligations, Maturities of Outstanding Principal Amount, Year One

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Insured Financial Obligations, Maturities of Outstanding Principal Amount, Year Ten to Fourteen

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Insured Financial Obligations, Maturities of Outstanding Contractual Payments [Abstract]

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Insured Financial Obligations, Maturities of Outstanding Contractual Payments, First Quarter After Period End

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Insured Financial Obligations, Maturities of Outstanding Contractual Payments, Second Quarter After Period End

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Insured Financial Obligations, Maturities of Outstanding Contractual Payments, Third Quarter After Period End

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Insured Financial Obligations, Maturities of Outstanding Contractual Payments, Year Four

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Insured Financial Obligations, Maturities of Outstanding Contractual Payments, Year Three

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Insured Financial Obligations, Maturities of Outstanding Principal Amount, First Quarter After Period End

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Insured Financial Obligations, Maturities of Outstanding Principal Amount, Second Quarter After Period End

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Insured Financial Obligations, Maturities of Outstanding Principal Amount, Third Quarter After Period End

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Insured Financial Obligations, Maturities of Outstanding Principal Amount, Year Four

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Insured Financial Obligations, Maturities of Outstanding Principal Amount, Year Three

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Insured Financial Obligations, Maturities of Outstanding Principal Amount, Year Two

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Represents the outstanding principal amounts of the underlying insured obligations for financial guaranty contracts, after netting out ceded contracts.

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