Annual report pursuant to Section 13 and 15(d)

Deferred Compensation And Retirement Plans - Fair Value Measurements of Defined Benefit Plan Assets (Detail)

v3.19.2
Deferred Compensation And Retirement Plans - Fair Value Measurements of Defined Benefit Plan Assets (Detail) - Deferred Compensation and Pension Plans - USD ($)
$ in Thousands
Apr. 30, 2019
Apr. 30, 2018
Defined Benefit Plan Disclosure [Line Items]    
Total defined benefit plan assets $ 25,131 $ 26,090
Mutual Funds    
Defined Benefit Plan Disclosure [Line Items]    
Total defined benefit plan assets 24,931 25,899
Money Market Funds    
Defined Benefit Plan Disclosure [Line Items]    
Total defined benefit plan assets 200 191
Fair Value, Inputs, Level 1    
Defined Benefit Plan Disclosure [Line Items]    
Total defined benefit plan assets 200 191
Fair Value, Inputs, Level 1 | Money Market Funds    
Defined Benefit Plan Disclosure [Line Items]    
Total defined benefit plan assets 200 191
Fair Value, Inputs, Level 2    
Defined Benefit Plan Disclosure [Line Items]    
Total defined benefit plan assets 24,931 25,899
Fair Value, Inputs, Level 2 | Mutual Funds    
Defined Benefit Plan Disclosure [Line Items]    
Total defined benefit plan assets $ 24,931 $ 25,899