Share repurchase program Share repurchase program (Details) - $ / shares	3 Months Ended	9 Months Ended
Mar. 31, 2016	Mar. 31, 2016	Oct. 22, 2014
Equity, Class of Treasury Stock
Stock Repurchase Program, Number of Shares Authorized to be Repurchased			35,000,000
Shares repurchased (in shares)	504,313	4,167,947
Treasury Stock Acquired, Average Cost Per Share	$ 99.14	$ 107.97

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

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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- 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

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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 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 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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