Credit Facilities (Details)	12 Months Ended
Jul. 31, 2017 USD ($) credit_facility	Jul. 31, 2017 EUR (€)	Jul. 31, 2016 USD ($)
Revolving credit facility
Line of Credit Facility [Line Items]
Outstanding borrowings on line of credit	$ 130,000,000
Uncommitted credit facilities
Line of Credit Facility [Line Items]
Number of uncommitted credit facilities \| credit_facility	2
Outstanding borrowings on line of credit	$ 19,200,000		$ 26,800,000
Weighted average interest rate	2.00%	2.00%	1.25%
Remaining borrowing capacity available on credit facilities	$ 45,700,000		$ 38,200,000
Treasury notes
Line of Credit Facility [Line Items]
Outstanding borrowings on line of credit	0		0
Maximum borrowing capacity available on line of credit	117,300,000	€ 100,000,000.0
Foreign line of credit
Line of Credit Facility [Line Items]
Outstanding borrowings on line of credit	0		0
Maximum borrowing capacity available on line of credit	51,000,000	€ 43,500,000.0
Other credit facilities
Line of Credit Facility [Line Items]
Outstanding borrowings on line of credit	$ 4,100,000		$ 8,700,000
Weighted average interest rate	0.32%	0.32%	0.32%
Remaining borrowing capacity available on credit facilities	$ 39,800,000		$ 45,500,000

Number Of Credit Facilities

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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- Definition

The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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(19))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Weighted average interest rate of short-term debt outstanding calculated at point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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