Share repurchase program Share repurchase program (Details) (USD $)	3 Months Ended	6 Months Ended
Dec. 31, 2014	Dec. 31, 2014	Oct. 22, 2014
Equity, Class of Treasury Stock
Share repurchased (in shares)	6,410,857us-gaap_TreasuryStockSharesAcquired	6,833,472us-gaap_TreasuryStockSharesAcquired
Treasury Stock Acquired, Average Cost Per Share	$ 127.39	$ 126.83
Subsequent Event
Stock Repurchase Program, Number of Shares Authorized to be Repurchased			35,000,000

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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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- Details

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

+ Details

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ 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 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

+ Details

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