Note 11 - Finance Lease Right-of-use Assets - Finance Lease Right-of-use Assets (Details) - USD ($) $ in Thousands	Jul. 31, 2019	Apr. 30, 2019
Right-of-use assets	$ 43,680	$ 1,699
Less accumulated depreciation	693
Total	42,987
Building [Member]
Right-of-use assets	$ 43,680