Note 10 - Accounting for the Costs of Computer Software Developed for Internal Use (Details Textual) - USD ($)	9 Months Ended
	Jan. 31, 2018	Jan. 31, 2017
Capitalized Computer Software, Additions	$ 0	$ 411,000
Internal Costs to Develop Software	215,000
Third Party Programmers Costs		196,000
Capitalized Computer Software, Amortization	$ 610,000	$ 3,558,000
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life	3 years
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life	5 years