Derivative Financial Instruments (Details 2) (USD $)	9 Months Ended	12 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Derivative Instruments, Gain (Loss)
Fair value of derivative liabilities	$ 3,282,000,000	$ 3,576,000,000
Derivative instruments designated as hedging instruments
Derivative Instruments, Gain (Loss)
Fair value of derivative liabilities	475,000,000	633,000,000
Derivative instruments not designated as hedging instruments
Derivative Instruments, Gain (Loss)
Fair value of derivative liabilities	84,000,000	373,000,000
Derivative instruments not designated as hedging instruments \| Foreign exchange forward and swap contracts
Derivative Instruments, Gain (Loss)
Notional amount	9,600,000,000	13,000,000,000
Maximum length of time hedged (in years)	less than 2Y
Derivative instruments not designated as hedging instruments \| Equity contracts
Derivative Instruments, Gain (Loss)
Notional amount	900,000,000	1,000,000,000
Derivative instruments not designated as hedging instruments \| Credit default swaps
Derivative Instruments, Gain (Loss)
Maximum length of time hedged (in years)	1Y or less
De-designated \| Derivative instruments in net investment hedging relationships
Derivative Instruments, Gain (Loss)
Notional amount		1,600,000,000
Fair value of derivative liabilities		221,000,000
Derivative instruments in fair value hedging relationships \| Interest rate swaps
Derivative Instruments, Gain (Loss)
Notional amount	6,700,000,000	7,100,000,000
Average remaining maturity	5.1Y	5.7Y
Derivative instruments in cash flow hedging relationships \| Interest rate swaps
Derivative Instruments, Gain (Loss)
Net gains (losses) in accumulated other comprehensive income in connection with cash flow hedges	(7,000,000)	(13,000,000)
Gains (losses) expected to be reclassified to net income within the next 12 months	(8,000,000)	(8,000,000)
Derivative instruments in cash flow hedging relationships \| Foreign exchange forward contracts
Derivative Instruments, Gain (Loss)
Notional amount	11,200,000,000	11,300,000,000
Average remaining maturity	0.6Y	0.8Y
Net gains (losses) in accumulated other comprehensive income in connection with cash flow hedges	183,000,000	(147,000,000)
Gains (losses) expected to be reclassified to net income within the next 12 months	195,000,000	(249,000,000)
Maximum length of time hedged (in years)	3.9Y
Derivative instruments in cash flow hedging relationships \| Currency swaps
Derivative Instruments, Gain (Loss)
Notional amount	100,000,000	200,000,000
Net gains (losses) in accumulated other comprehensive income in connection with cash flow hedges	(2,000,000)	(1,000,000)
Gains (losses) expected to be reclassified to net income within the next 12 months	(1,000,000)	(1,000,000)
Maximum length of time hedged (in years)	2.3Y
Derivative instruments in net investment hedging relationships
Derivative Instruments, Gain (Loss)
Notional amount	$ 2,000,000,000	$ 1,900,000,000
Average remaining maturity	0.2Y	0.4Y

Accumulated pretax change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges.

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- Definition

Monetary amount specified by the derivative(s). Expressed as an absolute value.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6887037&loc=d3e80748-113994

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- Definition

The average time remaining until maturity on the group of derivatives identified.

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- Definition

Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624163-113959

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph a

-Clause 1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 205G

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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.

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- Definition

Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6887037&loc=d3e80748-113994

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