Financial Guaranty Insurance Losses - Net Expected Loss to be Expensed Insurance Contracts (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015
Financial Guaranty Insurance Contracts, Premiums [Line Items]
2015 (April 1 - June 30)	$ 7
2015 (July 1 - September 30)	9
2015 (October 1 - December 31)	11
Subtotal 2015	27
2016	36
2017	27
2018	25
2019	23
2020-2024	77
2025-2029	45
2030-2034	34
After 2034	21
Net expected loss to be expensed	315
Discount	389
Total future value	$ 704

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

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- Definition

For financial guaranty insurance contracts, the amount of net loss expected to be expensed during the first quarter of the subsequent annual period following the statement of financial position reporting date.

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- Definition

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

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No definition available.

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- Definition

For financial guaranty insurance contracts, the amount of net loss expected to be expensed during the second quarter of the subsequent annual period following the statement of financial position reporting date.

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No definition available.

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- Definition

Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed During Third Quarter Following Balance Sheet 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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No definition available.

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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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No definition available.

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- Definition

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

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No definition available.

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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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No definition available.

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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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No definition available.

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- Definition

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

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No definition available.

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- Definition

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

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- Details

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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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