Face (par) amount of debt instrument at time of issuance.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

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Debt Issuance (Details) (USD $)	9 Months Ended
Debt Issuance (Details) (USD $)	Apr. 30, 2015	Apr. 16, 2015	Jun. 25, 2015
2.93% Senior Unsecured Notes Due April 16, 2025 [Member]
Debt Instrument [Line Items]
Senior unsecured notes, issued		$ 25,000,000
Senior unsecured notes, due date	Apr. 16, 2025
Senior unsecured notes, interest rate		2.93%
3.18% Senior Unsecured Notes Due June 17, 2030 [Member]
Debt Instrument [Line Items]
Senior unsecured notes, due date	Jun. 17, 2030
3.18% Senior Unsecured Notes Due June 17, 2030 [Member] \| Scenario, Forecast [Member]
Debt Instrument [Line Items]
Senior unsecured notes, issued			$ 125,000,000
Senior unsecured notes, interest rate			3.18%