REVENUE RECOGNITION (Deferred Revenue) (Details) - USD ($) $ in Thousands	9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020
Movement in Deferred Revenue [Roll Forward]
Balance, end of the period	$ 18,700
POM
Movement in Deferred Revenue [Roll Forward]
Balance, end of the period	135,100
POM | Deferred Revenue
Movement in Deferred Revenue [Roll Forward]
Balance, beginning of the period	183,685	$ 212,511
Amounts deferred	35,977	28,686
Amounts recognized on previous deferrals	(84,573)	(87,850)
Balance, end of the period	135,089	153,347
POM | Deferred Wages
Movement in Deferred Revenue [Roll Forward]
Balance, beginning of the period	21,618	27,306
Amounts deferred	1,118	1,827
Amounts recognized on previous deferrals	(9,652)	(12,134)
Balance, end of the period	$ 13,084	$ 16,999