Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph l

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 350

-SubTopic 20

-Section 50

-Paragraph 1

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-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 72

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

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-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 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 34

-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.

+ Details

- Definition

The aggregate amount of goodwill acquired in the period and allocated to the reportable segment. The value is stated at fair value based on the purchase price allocation.

+ References+ Details

Goodwill and Other Intangible Assets - Changes in the Carrying Amount of Goodwill by Reportable Segment (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended				6 Months Ended				6 Months Ended				6 Months Ended				6 Months Ended				6 Months Ended				6 Months Ended				3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Dec. 31, 2011	Jun. 30, 2013 Retail Banking [Member]	Jun. 30, 2012 Retail Banking [Member]	Dec. 31, 2012 Retail Banking [Member]	Dec. 31, 2011 Retail Banking [Member]	Jun. 30, 2013 Diversified Commercial Banking [Member]	Jun. 30, 2012 Diversified Commercial Banking [Member]	Dec. 31, 2012 Diversified Commercial Banking [Member]	Dec. 31, 2011 Diversified Commercial Banking [Member]	Jun. 30, 2013 Corporate and Investment Banking [Member]	Jun. 30, 2012 Corporate and Investment Banking [Member]	Dec. 31, 2012 Corporate and Investment Banking [Member]	Dec. 31, 2011 Corporate and Investment Banking [Member]	Jun. 30, 2013 Wealth and Investment Management [Member]	Jun. 30, 2012 Wealth and Investment Management [Member]	Dec. 31, 2012 Wealth and Investment Management [Member]	Dec. 31, 2011 Wealth and Investment Management [Member]	Jun. 30, 2013 Consumer Banking and Private Wealth Management [Member]	Jun. 30, 2012 Consumer Banking and Private Wealth Management [Member]	Dec. 31, 2012 Consumer Banking and Private Wealth Management [Member]	Dec. 31, 2011 Consumer Banking and Private Wealth Management [Member]	Jun. 30, 2013 Wholesale Banking [Member]	Jun. 30, 2012 Wholesale Banking [Member]	Dec. 31, 2012 Wholesale Banking [Member]	Dec. 31, 2011 Wholesale Banking [Member]	Jun. 30, 2013 Consumer Banking and Private Wealth Management [Member] Wholesale Banking [Member]
Goodwill [Line Items]
Goodwill, Allocation Adjustment	$ 0	$ 0			$ 0	$ (4,854)			$ 0	$ (928)			$ 0	$ (180)			$ 0	$ (382)			$ 300	$ 3,930			$ (300)	$ 2,414			$ 300
Goodwill	6,369	6,376	6,369	6,344	0	0	0	4,854	0	0	0	928	0	0	0	180	0	0	0	382	4,262	3,962	3,962	0	2,107	2,414	2,407	0
Goodwill, Acquired During Period		$ 32				$ 0				$ 0				$ 0				$ 0				$ 32				$ 0