COMMITMENTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2016	Apr. 30, 2015
Operating Leased Assets [Line Items]
Total rental expense	$ 5,117	$ 5,030
Minimum lease and rent agreement commitments [Abstract]
2016	5,027
2017	5,016
2018	4,929
2019	4,946
2020	4,995
Operating lease future minimum payments due	$ 24,913
3 Year Initial Term [Member]
Operating Leased Assets [Line Items]
Initial lease term	3 years
5 Year Initial Term [Member]
Operating Leased Assets [Line Items]
Initial lease term	5 years
10 Year Initial Term [Member]
Operating Leased Assets [Line Items]
Initial lease term	10 years
25 Year Initial Term [Member]
Operating Leased Assets [Line Items]
Initial lease term	25 years