Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The period by which the reporting for a given investment lags behind the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Hedge effectiveness, percentage.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of the cumulative effect of the change in accounting principle or new accounting pronouncement on deferred acquisition costs in the statement of financial position as of the beginning of the earliest period presented.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of the cumulative effect of the change in accounting principle or new accounting pronouncement on deferred tax liability in the statement of financial position as of the beginning of the earliest period presented.

+ References

No definition available.

+ Details

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- Definition

Amount of the cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

+ References

No definition available.

+ Details

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- Definition

The percentage ownership threshold in a given investment, if exceeded, indicates that significant influence generally exists.

+ References

No definition available.

+ Details

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Significant Accounting Policies (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2013 Alternative funds	Dec. 31, 2013 Private investment funds	Dec. 31, 2013 Operating affiliates	Dec. 31, 2013 Investments in the common stock of a corporation	Dec. 31, 2013 Investments in closed end funds, limited partnerships, LLCs or similar investment vehicles	Dec. 31, 2013 Maximum	Dec. 31, 2013 Minimum	Dec. 31, 2011 Accounting Standards Update 2010-26 [Member]
Significant Accounting Policies [Line Items]
Alternative investments, timelag for reporting		1 month	3 months	3 months
Threshold for signicant influence, percentage					20.00%	3.00%
Hedge effectiveness, percentage							125.00%	80.00%
Options, life of award	10 years
Vesting period required							4 years	3 years
Deferred tax liability, cumulative adjustment effect									$ 7
Deferred acquisition costs, cumulative adjustment effect									21
Net assets, cumulative adjustment effect									$ 14