NOTE J - RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS (Details) - USD ($)	3 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	May 01, 2018
NOTE J - RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS (Details) [Line Items]
Contract with Customer, Liability, Revenue Recognized	$ 9,300,000
Revenues	11,011,000	$ 12,023,000
Accounting Standards Update 2014-09 [Member]
NOTE J - RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS (Details) [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	484,000
Revenues	$ 811,000
Assets [Member] | Accounting Standards Update 2014-09 [Member]
NOTE J - RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS (Details) [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			$ 87,000
Liabilities, Total [Member] | Accounting Standards Update 2014-09 [Member]
NOTE J - RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS (Details) [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			109,000
Retained Earnings [Member] | Accounting Standards Update 2014-09 [Member]
NOTE J - RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS (Details) [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			$ 22,000