Credit Quality of Loans and Allowance for Loan Losses - Nonaccrual Loans, Interest Income Data (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Credit Quality of Loans and Allowance for Loan Losses [Abstract]
Interest income that would have been recorded if loans had been performing in accordance with original terms	$ 125	$ 150
Interest income that was recorded on nonaccrual loans during the fiscal year ended	$ 29	$ 54

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

Name:	us-gaap_LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration