Contracts Accounted for as Insurance - Net Expected Loss to be Expensed Insurance Contracts (Details) $ in Millions	Sep. 30, 2019 USD ($)
Insurance [Abstract]
2019 (October 1 - December 31)	$ 9
2020	37
2021	36
2022	35
2023	31
2024-2028	147
2029-2033	99
2034-2038	45
After 2038	9
Net expected loss to be expensed	448
Future accretion	30
Total expected future loss and LAE	$ 478

Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed Beyond Twentieth Fiscal Year

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- Definition

Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed During Fourth Quarter Following Balance Sheet Date

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- Definition

Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed More than 10 and within 15 Years from Balance Sheet Date

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- Definition

Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed More than 15 and within 20 Years from Balance Sheet Date

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- Definition

For financial guarantee insurance contracts, the amount of net loss expected to be expensed during the sixth through tenth year following the statement of financial position reporting date.

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- Definition

Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed in Fifth Full Fiscal Year

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- Definition

For financial guarantee insurance contracts, the amount of net loss expected to be expensed within the fourth full fiscal year following the date of the latest balance sheet presented in the financial statements.

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- Definition

For financial guaranty insurance contracts, the amount of net loss expected to be expensed within the second full fiscal year following the date of the latest balance sheet presented in the financial statements.

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Financial Guarantee Insurance Contracts, Future Expected, Net Loss to be Expensed in Third Full Fiscal Year

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- Definition

Financial Guarantee Insurance Contracts, Net Loss to be Expensed, Present Value

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- Definition

Financial Guarantee Insurance Contracts, Net Loss to be Expensed, Undiscounted

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- Definition

Schedule of Insured Financial Obligations with Credit Deterioration, Reductions of Gross Claim Liability, Net of Reinsurance Recoverable, Discount

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