Loans and asset quality- Troubled Debt Restructurings (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Sep. 30, 2014 Contract	Jun. 30, 2014 Contract	Sep. 30, 2013 Contract
Financing Receivable, Modifications [Line Items]
Number of contracts (contracts)	27	29	34
Outstanding recorded investment Pre-modification	$ 4	$ 5	$ 8
Outstanding recorded investment Post- modification	5	6	9
Domestic \| Other residential mortgages
Financing Receivable, Modifications [Line Items]
Number of contracts (contracts)	27	28	34
Outstanding recorded investment Pre-modification	4	5	8
Outstanding recorded investment Post- modification	5	6	9
Domestic \| Wealth management loans and mortgages
Financing Receivable, Modifications [Line Items]
Number of contracts (contracts)	0	1	0
Outstanding recorded investment Pre-modification	0	0	0
Outstanding recorded investment Post- modification	$ 0	$ 0	$ 0

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953676-111524

+ Details

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

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