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Deferred Compensation And Retirement Plans - Reconciliation Of Benefit Obligation (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Apr. 30, 2021 | Apr. 30, 2020 | Apr. 30, 2019
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Total benefit obligation |  | $ 364,793 | $ 308,279 |
Deferred Compensation Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Benefit obligation, beginning of year |  | 180,821 | 148,369 |
Service cost |  | 31,947 | 24,939 | $ 17,281
Interest cost |  | 4,035 | 5,433 | 5,044
Actuarial (gain) loss |  | (590) | 13,427 |
Administrative expenses paid |  | (265) | (155) |
Benefits paid from plan assets |  | (2,327) | (3,932) |
Benefits paid from cash |  | (7,881) | (6,652) |
Plan amendment |  |  | (608) |
Benefit obligation, end of year |  | 205,740 | 180,821 | 148,369
Fair value of plan assets, beginning of year |  | 24,235 | 25,131 |
Actual return on plan assets |  | 4,523 | 2,726 |
Benefits paid from plan assets |  | (2,327) | (3,932) |
Administrative expenses paid |  | (265) | (155) |
Employer contributions |  | 580 | 465 |
Fair value of plan assets, end of year |  | 26,746 | 24,235 | 25,131
Funded status and balance, end of year | [1] | (178,994) | (156,586) |
Current liability |  | 9,074 | 8,887 |
Non-current liability |  | 169,920 | 147,699 |
Total benefit obligation |  | $ 178,994 | $ 156,586 |
Plan assets weighted average allocation |  | 100.00% | 100.00% |
Deferred Compensation Plan | Debt Securities |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Plan assets weighted average allocation |  | 36.00% | 43.00% |
Deferred Compensation Plan | Equity Securities |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Plan assets weighted average allocation |  | 62.00% | 56.00% |
Deferred Compensation Plan | Other securities |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Plan assets weighted average allocation |  | 2.00% | 1.00% |
Executive Capital Accumulation Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Benefit obligation, beginning of year |  | $ 129,315 | $ 130,161 |
Employee contributions |  | 4,935 | 8,215 |
Amortization of employer contributions |  | 6,287 | 6,074 |
Gain on investment |  | 37,323 | (826) |
Benefits paid from cash |  | (15,652) | (13,911) |
Exchange rate fluctuations |  | 1,374 | (398) |
Benefit obligation, end of year |  | 163,582 | 129,315 | $ 130,161
Current liability |  | 8,663 | 9,590 |
Non-current liability |  | 154,919 | 119,725 |
Total benefit obligation |  | $ 163,582 | $ 129,315 |
[1] | The Company purchased COLI contracts insuring the lives of certain employees eligible to participate in the deferred compensation and pension plans as a means of funding benefits under such plans. As the COLI contracts are held in trust and are not separated from our general corporate assets, they are not included in the funded status. As of April 30, 2021 and 2020, the Company held contracts with gross CSV of $241.3 million and $238.7 million, offset by outstanding policy loans of $80.0 million and $92.3 million, respectively

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