Expected Loss to be Paid - Components of Development and Accretion Amounts of Estimated Recoveries (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Expected Losses [Abstract]
Inclusion or removal of deals with breaches of R&W during period	$ 0	$ 6
Change in recovery assumptions as the result of recovery success	31	(6)
Estimated increase (decrease) in defaults that will result in additional (lower) breaches	(37)	(8)
Settlements and anticipated settlements	263	289
Accretion of discount on balance	11	15
Total	$ 268	$ 296

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Represents the change in the estimate of recoveries on defaulted insured obligations with breached representations and warranties resulting from accretion of discount.

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No definition available.

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- Definition

Represents the change in the estimate of recoveries on defaulted insured obligations with breached representations and warranties related to the inclusion of new transaction with breaches during the period.

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No definition available.

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- Definition

Represents the change in the estimate of recoveries on defaulted insured obligations with breached representations and warranties resulting from additional file review and recovery success.

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No definition available.

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- Definition

Represents the development and accretion of discount during the period related to the estimated recoveries for breached representations and warranties.

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No definition available.

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- Definition

Represents the change in the estimate of recoveries on defaulted insured obligations with breached representations and warranties resulting from an estimated increase in defaults that will result in additional breaches.

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No definition available.

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- Definition

Represents the increase in the estimate of recoveries on defaulted insured obligations with breached representations and warranties related to the achievement of negotiated agreements.

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No definition available.

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