NOTE J - CREDIT FACILITY (Details) - JP Morgan Chase Bank, N.A. [Member] - Line of Credit [Member] $ in Millions	9 Months Ended
Jan. 31, 2016 USD ($)
NOTE J - CREDIT FACILITY (Details) [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 25.0
Line of Credit Facility, Borrowing Capacity, Description	Pursuant to the Credit Agreement, the amount of Tranche A borrowings may not exceed the value of the Pledged Investments (as defined in the Credit Agreement). The amount of Tranche B borrowings may not exceed the lesser of (i) $15.0 million and (ii) the Borrowing Base (as defined in the Credit Agreement).
Line of Credit Facility, Collateral	The Facility is fully guaranteed by certain of the Company’s subsidiaries and is secured by, among other things, a pledge of substantially all personal property of the Company and certain of the Company’s subsidiaries.
Line of Credit Facility, Expiration Date	Jun. 05, 2018
Line of Credit Facility, Commitment Fee Percentage	0.10%
Debt Instrument, Tranche B [Member]
NOTE J - CREDIT FACILITY (Details) [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 15.0
Debt Instrument, Tranche B [Member] \| London Interbank Offered Rate (LIBOR) [Member]
NOTE J - CREDIT FACILITY (Details) [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.75%
Debt Instrument, Tranche A [Member]
NOTE J - CREDIT FACILITY (Details) [Line Items]
Long-term Line of Credit	$ 6.0
Debt Instrument, Tranche A [Member] \| London Interbank Offered Rate (LIBOR) [Member]
NOTE J - CREDIT FACILITY (Details) [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.75%

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

+ References

No definition available.

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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 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-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 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 SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

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- Definition

Description of the credit facility's borrowing capacity including discussion of how the borrowing capacity is determined (for example, borrowing capacity based on the amount of current assets).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 22
-Article 5

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- Definition

Discussion of whether the borrowings under the credit facility are secured or unsecured and, if secured, a description of collateral (for example, accounts receivable less than 120 days old, finished goods inventory).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(b))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 22
-Article 5

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ 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

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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

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