Fair Value Inputs, Correlation Risk

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ 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 (e)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ 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 (d)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ 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 (c)(1)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ 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 (c)(2)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ 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 (c)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Fair value of financial and nonfinancial obligations.

+ 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=25499696&loc=d3e19207-110258

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Fair Value Measurement- Quantitative Information about Level 3 Fair Value Measurements of Liabilities (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012	Dec. 31, 2011
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	$ 92	$ 300	$ 92	$ 300	$ 117	$ 224	$ 302	$ 314
Included in earnings (or changes in net liabilities)	(5)		(110)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	7	2	5	14
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	(1)	12	27	33
Fair Value, Measurements, Recurring \| Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair value of liabilities	92		92			224
Fair Value, Measurements, Recurring \| Level 3 \| Trading Liabilities \| Structured Foreign Exchange Swaptions \| Option Pricing Model
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair value of liabilities	53		53
Fair Value, Measurements, Recurring \| Level 3 \| Trading Liabilities \| Structured Foreign Exchange Swaptions \| Option Pricing Model \| Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Correlation risk (percent)			0.00%
Volatility (percent)			12.00%
Fair Value, Measurements, Recurring \| Level 3 \| Trading Liabilities \| Structured Foreign Exchange Swaptions \| Option Pricing Model \| Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Correlation risk (percent)			25.00%
Volatility (percent)			16.00%
Fair Value, Measurements, Recurring \| Level 3 \| Trading Liabilities \| Equity Options \| Option Pricing Model
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair value of liabilities	$ 39		$ 39
Fair Value, Measurements, Recurring \| Level 3 \| Trading Liabilities \| Equity Options \| Option Pricing Model \| Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Volatility (percent)			23.00%
Fair Value, Measurements, Recurring \| Level 3 \| Trading Liabilities \| Equity Options \| Option Pricing Model \| Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Volatility (percent)			28.00%