Financing Agreements - (Details) $ in Thousands	12 Months Ended
Apr. 30, 2016 USD ($)
Line of Credit Facility [Line Items]
Debt instrument, actual, fixed charge coverage ratio	(1500.00%)
Debt instrument, actual, interest-bearing debt, ratio	7.00%
Line of Credit
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 35,000
Effective interest rate	2.40%
Line of credit facility, unused capacity, commitment fee percentage	0.125%
Debt instrument, restrictive covenants, fixed charge coverage ratio	200.00%
Debt instrument, restrictive covenants, capital expenditure reserve, amount	$ 6,000
Debt instrument, restrictive covenants, interest-bearing debt, ratio	100.00%
Standby Letters of Credit
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 15,000
Line of Credit Facility, Amount Outstanding	3,872
Foreign Line of Credit
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 40,000
Effective interest rate	1.50%
Line of credit facility, unused capacity, commitment fee percentage	15.00%
Debt instrument, restrictive covenants, fixed charge coverage ratio	200.00%
Debt instrument, restrictive covenants, capital expenditure reserve, amount	$ 6,000
Debt instrument, restrictive covenants, interest-bearing debt, ratio	100.00%
Bank Guarantees
Line of Credit Facility [Line Items]
Line of Credit Facility, Amount Outstanding	$ 3,482
LIBOR \| Minimum \| Line of Credit
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	145.00%
LIBOR \| Maximum \| Line of Credit
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	195.00%

Debt Instrument, Actual, Fixed Charge Coverage Ratio

No definition available.

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- Definition

Debt Instrument, Actual, Interest-Bearing Debt, Ratio

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Restrictive Covenants, Capital Expenditure Reserve, Amount

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Debt Instrument, Restrictive Covenants, Fixed Charge Coverage Ratio

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Restrictive Covenants, Interest-Bearing Debt, Ratio

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions 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 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: 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(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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