Outstanding Exposure - Amortization Schedule of Puerto Rico Net Par Outstanding and Net Debt Service Outstanding (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Scheduled Net Par Amortization
Total	$ 248,144	$ 249,153
Scheduled Net Debt Service Amortization
Total	394,849	397,636
Puerto Rico
Scheduled Net Par Amortization
2024 (April 1 - June 30)	0
2024 (July 1 - September 30)	110
2024 (October 1 - December 31)	0
Subtotal 2024	110
2025	84
2026	140
2027	120
2028	81
2029-2033	197
2034-2038	132
2039-2041	97
Total	961	$ 1,105
Scheduled Net Debt Service Amortization
2024 (April 1 - June 30)	3
2024 (July 1 - September 30)	131
2024 (October 1 - December 31)	3
Subtotal 2024	137
2025	124
2026	177
2027	151
2028	106
2029-2033	281
2034-2038	170
2039-2041	106
Total	$ 1,252

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

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