Leases (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020
Leases
Option to extend			true
Finance lease cost:
Amortization of right-of-use assets	$ 5,898	$ 6,007	$ 17,997	$ 18,120
Interest on lease liabilities	2,748	3,300	8,673	10,089
Operating lease cost	10,601	10,646	31,930	31,555
Variable lease cost	3,197	3,311	9,329	9,924
Total lease cost	$ 22,444	$ 23,264	$ 67,929	$ 69,688
Minimum
Leases
Lease term (in years)	1 year		1 year
Renewal lease term (in years)	1 year		1 year
Maximum
Leases
Lease term (in years)	11 years		11 years
Renewal lease term (in years)	5 years		5 years