Commitments and Contingent Liabilities (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Sep. 30, 2013	Jun. 30, 2013	Sep. 30, 2012	Jun. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Loss Contingencies [Line Items]
Litigation charges	$ 35		$ 44		$ 50	$ 60
Average Wholesale Price Litigation [Member]
Loss Contingencies [Line Items]
Litigation charges	$ 35	$ 15	$ 44	$ 16	$ 50	$ 60

The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Name:	us-gaap_LossContingencyLossInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration