v2.4.0.8

Fair Value Measurements (Fair Value And Maximum Future Funding Commitments Related To Investments) (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013
Fair Value [Member]
Fair Value And Maximum Future Funding Commitments Related To Investments [Line Items]
Financial	$ 266	$ 256
Real estate	304	322
Distressed	289	180
Mezzanine	300	276
Traditional	960	813
Vintage	10	13
Investment funds	384	428
Total of alternative investments	2,513	2,288
Maximum Future Funding Commitments [Member]
Fair Value And Maximum Future Funding Commitments Related To Investments [Line Items]
Financial	127	129
Real estate	43	92
Distressed	132	230
Mezzanine	213	252
Traditional	388	456
Vintage	0	0
Total of alternative investments	$ 903	$ 1,159
Expected Liquidation Period Lower Range [Member]
Fair Value And Maximum Future Funding Commitments Related To Investments [Line Items]
Liquidation period for financial alternative investments (in years)	5 years	5 years
Liquidation period for real estate alternative investments (in years)	3 years	3 years
Liquidation period for distressed alternative investments (in years)	6 years	6 years
Liquidation period for mezzanine alternative investments (in years)	6 years	6 years
Liquidation period for traditional alternative investments (in years)	3 years	3 years
Liquidation period for vintage alternative investments (in years)	1 year	1 year
Expected Liquidation Period Upper Range [Member]
Fair Value And Maximum Future Funding Commitments Related To Investments [Line Items]
Liquidation period for financial alternative investments (in years)	9 years	9 years
Liquidation period for real estate alternative investments (in years)	9 years	9 years
Liquidation period for distressed alternative investments (in years)	9 years	9 years
Liquidation period for mezzanine alternative investments (in years)	9 years	9 years
Liquidation period for traditional alternative investments (in years)	8 years	8 years
Liquidation period for vintage alternative investments (in years)	3 years	3 years

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Alternative investments - Distressed consists of investments in private equity funds targeting distressed debt/credit and equity opportunities in the US.

+ References

No definition available.

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Alternative investments - Financial primarily consists of investments in private equity funds targeting financial services companies.

+ References

No definition available.

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- Definition

Alternative investments - Investment funds employ various investment strategies such as long/short equity and arbitrage/distressed.

+ References

No definition available.

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- Definition

Alternative investments - Mezzanine consists of investments in private equity funds targeting private mezzanine debt of large cap and mid cap companies in the US and worldwide.

+ References

No definition available.

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Alternative investments - Real Estate consists of investments in private equity funds targeting global distress opportunities, value added US properties, and global mezzanine debt securities in the commercial real estate market.

+ References

No definition available.

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Total of alternative investments.

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No definition available.

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- Definition

Alternative investments - Traditional consists of investments in private equity funds employing traditional private equity investment strategies such as buyout and venture with different geographical focuses including Brazil, India, Asia, Europe, and the US.

+ References

No definition available.

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- Definition

Alternative investments - Vintage consists of investments in private equity funds made before 2002 and where the funds' commitment periods had already expired.

+ References

No definition available.

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Liquidation period in years for distressed alternative investments (consists of investments in private equity funds targeting distressed debt/credit and equity opportunities in the US.)

+ References

No definition available.

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Liquidation period in years for financial alternative investments (primarily consists of investments in private equity funds targeting financial services companies).

+ References

No definition available.

+ Details

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- Definition

Liquidation period in years for mezzanine alternative investments (consists of investments in private equity funds targeting private mezzanine debt of large cap and mid cap companies in the US and worldwide).

+ References

No definition available.

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Liquidation period in years for real estate alternative investments (consists of investments in private equity funds targeting global distress opportunities, value added US properties, and global mezzanine debt securities in the commercial real estate market).

+ References

No definition available.

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- Definition

Liquidation period in years for traditional alternative investments (consists of investments in private equity funds employing traditional private equity investment strategies such as buyout and venture with different geographical focuses including Brazil, India, Asia, Europe, and the US.)

+ References

No definition available.

+ Details

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- Definition

Liquidation period in years for vintage alternative investments (consists of investments in private equity funds made before 2002 and where the funds' commitment periods had already expired.)

+ References

No definition available.

+ Details

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