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Fair value measurement with unobservable inputs reconciliation recurring basis asset and liabilities value.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) recognized in earnings, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

+ References

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- Definition

Purchases that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

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- Definition

Sales that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

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- Definition

Settlements that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

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- Definition

Transfers into assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

+ References

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- Definition

Transfers out of assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

+ References

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- Definition

Amount of gain (loss) recognized in earnings, arising from liabilities measured at fair value on a recurring basis using 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 (c)(1)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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Fair Value Measurements - Change in Fair Values of Level 3 Financial Instruments (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended			3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended			3 Months Ended		9 Months Ended
	Sep. 30, 2013 Trading Account Assets [Member] Other Mortgage-Backed Securities [Member]	Sep. 30, 2012 Trading Account Assets [Member] Other Mortgage-Backed Securities [Member]	Jun. 30, 2012 Trading Account Assets [Member] Other Mortgage-Backed Securities [Member]	Sep. 30, 2013 Trading Account Assets [Member] Other Securities [Member]	Sep. 30, 2012 Trading Account Assets [Member] Other Securities [Member]	Sep. 30, 2013 Trading Account Assets [Member] Other Securities [Member]	Sep. 30, 2012 Trading Account Assets [Member] Other Securities [Member]	Sep. 30, 2013 Trading Account Assets [Member] States and Political Subdivisions [Member]	Sep. 30, 2013 Other Investments [Member] Principal Investments Direct [Member]	Sep. 30, 2012 Other Investments [Member] Principal Investments Direct [Member]	Sep. 30, 2013 Other Investments [Member] Principal Investments Direct [Member]	Sep. 30, 2012 Other Investments [Member] Principal Investments Direct [Member]	Sep. 30, 2013 Other Investments [Member] Principal Investments Indirect [Member]	Sep. 30, 2012 Other Investments [Member] Principal Investments Indirect [Member]	Sep. 30, 2013 Other Investments [Member] Principal Investments Indirect [Member]	Sep. 30, 2012 Other Investments [Member] Principal Investments Indirect [Member]	Sep. 30, 2013 Other Investments [Member] Equity and Mezzanine Investments Direct [Member]	Sep. 30, 2012 Other Investments [Member] Equity and Mezzanine Investments Direct [Member]	Sep. 30, 2013 Other Investments [Member] Equity and Mezzanine Investments Direct [Member]	Sep. 30, 2012 Other Investments [Member] Equity and Mezzanine Investments Direct [Member]	Sep. 30, 2013 Other Investments [Member] Equity and Mezzanine Investments Indirect [Member]	Sep. 30, 2012 Other Investments [Member] Equity and Mezzanine Investments Indirect [Member]	Sep. 30, 2013 Other Investments [Member] Equity and Mezzanine Investments Indirect [Member]	Sep. 30, 2012 Other Investments [Member] Equity and Mezzanine Investments Indirect [Member]	Sep. 30, 2013 Interest Rate [Member]	Sep. 30, 2012 Interest Rate [Member]	Sep. 30, 2013 Interest Rate [Member]	Sep. 30, 2012 Interest Rate [Member]	Sep. 30, 2013 Energy and Commodity [Member]	Sep. 30, 2013 Energy and Commodity [Member]	Sep. 30, 2012 Energy and Commodity [Member]	Jun. 30, 2012 Energy and Commodity [Member]	Sep. 30, 2013 Credit [Member]	Sep. 30, 2012 Credit [Member]	Sep. 30, 2013 Credit [Member]	Sep. 30, 2012 Credit [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance		$ 35	$ 1		$ 57			$ 3	$ 186	$ 231	$ 191	$ 225	$ 426	$ 482	$ 436	$ 473		$ 18		$ 15	$ 32	$ 43	$ 41	$ 36	$ 25	$ 35	$ 19	$ 38	$ 1	$ 1	$ (1)	$ (1)	$ 4	$ 5	$ 4	$ (21)
Gains (Losses) Included in Earnings	4	2		1	4	4	2		(4)	4	(9)	12	18	7	37	50				3	(1)		1	6	(7)	(2)	(10)	(5)	(2)	(2)	1		(3)	(4)	(6)	(11)
Purchases									3	1	7	11	3	4	14	24								4				1			(1)
Sales	(4)	(32)						(3)	(17)	(22)	(21)	(34)	(30)	(38)	(70)	(92)										(6)	(1)	(7)
Settlements				(1)	(5)	(4)	(3)											(18)		(18)	(3)		(14)	(4)									2	4	5	37
Transfers into Level 3							57															(1)				3	39	7
Transfers out of Level 3		(4)																							1	(7)	(28)	(11)
Ending Balance		1	1		56		56		168	214	168	214	417	455	417	455					28	42	28	42	19	23	19	23	(1)	(1)	(1)	(1)	3	5	3	5
Unrealized Gains (Losses) Included in Earnings				$ (2)	$ 4	$ (1)	$ 2		$ (8)	$ 2	$ (19)	$ 10	$ 9	$ (7)	$ 13	$ 21	$ 5	$ 5	$ 8	$ 15	$ (1)		$ 1	$ 6