Leases - Additional Information (Details)		12 Months Ended
	Aug. 24, 2020 USD ($) Installment	Apr. 30, 2021 USD ($)	Apr. 30, 2020 USD ($)
Lessee Lease Description [Line Items]
Operating lease cost		$ 3,100,000
Short-term operating lease costs		$ 263,000
Operating lease, weighted average lease term		16 years 8 months 12 days
Operating lease, weighted average discount rate		5.30%
Operating right-of-use lease asset		$ 25,375,000	$ 2,772,000
Operating lease, liability		26,551,000
Cash paid for amounts included in measurement of liabilities and operating cash flows		1,500,000
Corporate Headquarters
Lessee Lease Description [Line Items]
Operating sublease, term of contract	18 years
Percentage of fair market value of subleased building space	90.00%
Operating right-of-use lease asset	$ 24,500,000
Operating lease, liability	$ 24,500,000
Operating lease, effective interest rate	5.40%
Number of monthly installments | Installment	216
Office Space
Lessee Lease Description [Line Items]
Reduction of Right-Of-Use asset		640,000
Reduction of lease liability		640,000
Office Space | Bentonville, Arkansas
Lessee Lease Description [Line Items]
Reduction of Right-Of-Use asset		240,000
Reduction of lease liability		240,000
Administrative Office Space
Lessee Lease Description [Line Items]
Operating right-of-use lease asset		369,000
Operating lease, liability		$ 369,000