Subsequent Events: (Details) (USD $)	3 Months Ended	1 Months Ended	3 Months Ended
Sep. 30, 2012 Litigation in United Kingdom regarding defined benefit plans (C Plan)	Oct. 31, 2012 Subsequent event	Sep. 30, 2012 Subsequent event Litigation in United Kingdom regarding defined benefit plans (C Plan)
Subsequent events:
Additional pre-tax retirement-related obligation recorded	$ 162,000,000		$ 162,000,000
Dividend declared (in dollars per share)		$ 0.85
Dividend declared, date		Oct. 30, 2012
Dividend payable, date		Dec. 10, 2012
Shareholders of record, date		Nov. 09, 2012
Additional amount authorized under stock repurchase program		$ 5,000,000,000

The additional amount authorized by an entity's Board of Directors under a stock repurchase plan.

No definition available.

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

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- Definition

Amount of other defined benefit plan costs.

+ References

No definition available.

+ Details

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 32

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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