Employee Benefit and Retirement Plans (Narrative) (Details)	12 Months Ended
	Apr. 30, 2022 USD ($) plan	Apr. 30, 2021 USD ($)	Apr. 30, 2020 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Recognized expenses for profit-sharing contributions	$ 800,000	$ 2,900,000	$ 3,700,000
401(k) contributions, percent match of employee's annual contribution			100.00%
Effective maximum contribution of base earnings			4.00%
Number of defined benefit pension plans | plan	2
Accumulated other comprehensive loss, net of tax	$ (10,225,000)	54,568,000
Accumulated benefit obligation	0	196,500,000
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 0	500,000
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Percent of after tax earnings contributed in profit sharing	0.00%
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Percent of after tax earnings contributed in profit sharing	5.00%
401(k) Plan [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expense for 401(k) matching contributions	$ 11,700,000	$ 11,900,000	$ 10,100,000