Acquisition of Radian Asset Assurance Inc. - Acquisition Costs (Details) - Radian [Member] $ in Millions	9 Months Ended
Sep. 30, 2015 USD ($)
Business Acquisition [Line Items]
Professional services	$ 2
Financial Advisory fees	10
Total	$ 12

Business Combination, Acquisition Related Financial Advisory Fees

No definition available.

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- Definition

Business Combination, Acquisition Related Professional Services Costs

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e1043-128460

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