Equity and Noncontrolling Interests Equity and Noncontrolling Interests - Additional Information (Details) (USD $)	3 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount	$ 3,650,000,000
Stock repurchases	600,000,000	1,199,000,000
Authorization in November 2013
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount		$ 3,000,000,000

The cash outflow to reacquire common stock during the period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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