Leases (Lease Costs) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Oct. 31, 2019	Oct. 31, 2019
Leases [Abstract]
Operating lease costs	$ 60,759	$ 120,930
Variable lease costs	17,689	32,450
Subrental income	(336)	(685)
Total lease costs	$ 78,112	$ 152,695