Note 1 - Nature of Operations and Summary of Significant Accounting Policies (Details) - Property and equipment, estimated useful lives	3 Months Ended
	Jul. 31, 2013
Building and Building Improvements [Member]
Note 1 - Nature of Operations and Summary of Significant Accounting Policies (Details) - Property and equipment, estimated useful lives [Line Items]
Property and equipment, useful lives	39 years
Equipment [Member] | Minimum [Member]
Note 1 - Nature of Operations and Summary of Significant Accounting Policies (Details) - Property and equipment, estimated useful lives [Line Items]
Property and equipment, useful lives	3 years
Equipment [Member] | Maximum [Member]
Note 1 - Nature of Operations and Summary of Significant Accounting Policies (Details) - Property and equipment, estimated useful lives [Line Items]
Property and equipment, useful lives	8 years