Business and Basis of Presentation (Details) $ in Millions	6 Months Ended
Jun. 30, 2015 USD ($) Company	Dec. 31, 2014 USD ($)
Business Acquisition [Line Items]
Number of holding companies having public debt outstanding \| Company	2
Debt issuance cost	$ 5
Fair value of investments elected to calculate net asset per share	$ 74	$ 76

Represents the number of holding companies in the entity's organizational structure having outstanding public debt.

No definition available.

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- Definition

Fair value of investments in certain entities that calculate net asset value per share, including, but not limited to, by unit, membership interest, or other ownership interest. Investments include, but are not limited to, investments in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 6A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=SL6742756-110258

+ 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

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

+ References

No definition available.

+ Details

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