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Employee Benefit Plans (Details) - USD ($)	12 Months Ended
Employee Benefit Plans (Details) - USD ($)	Apr. 30, 2025	Apr. 30, 2024	Oct. 11, 2024
Employee Benefit Plans (Details) [Line Items]
Stock Issued During Period, Value, Employee Benefit Plan	$ 901,000	$ 514,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in Shares)	20,000	0
Noncash or Part Noncash Acquisition, Noncash Financial or Equity Instrument Consideration, Shares Issued (in Shares)	15,444
Shares Issued, Shares, Share-Based Payment Arrangement, before Forfeiture (in Shares)	1,550	3,300
Employee Benefits and Share-Based Compensation	$ 1,399,000	$ 756,000
Share-Based Payment Arrangement, Noncash Expense	1,161,000	822,000
Unrecognized stock compensation	4,200,000	2,900,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	918,000	521,000
Assets, Fair Value Disclosure	$ 7,000,000	$ 6,600,000
Common Stock [Member]
Employee Benefit Plans (Details) [Line Items]
Stock Issued During Period, Shares, Employee Benefit Plan (in Shares)	70,100	58,987
Stock Issued During Period, Value, Employee Benefit Plan	$ 70,000	$ 59,000
United States Post-Retirement Benefit Plan of US Entity, Defined Benefit [Member]
Employee Benefit Plans (Details) [Line Items]
Stock Issued During Period, Shares, Employee Benefit Plan (in Shares)	70,100	58,987
Stock Issued During Period, Value, Employee Benefit Plan	$ 901,000	$ 514,000
APIC, Share-Based Payment Arrangement, ESPP, Increase for Cost Recognition	$ 831,000	$ 455,000
Common Stock, Capital Shares Reserved for Future Issuance (in Shares)	504,734	495,395
Income Incentive Pool [Member]
Employee Benefit Plans (Details) [Line Items]
Accrued Bonuses	$ 1,800,000	$ 489,000
Deferred Compensation Agreement [Member]
Employee Benefit Plans (Details) [Line Items]
Deferred Compensation Arrangement with Individual, Description	Under these agreements, each key employee receives specified retirement payments for the remainder of the employee’s life with a minimum payment of ten years’ benefits to either the employee or his or her beneficiaries. The agreements also provide for lump sum payments upon termination of employment without cause and reduced benefits upon early retirement.
Deferred Compensation Arrangement with Individual, Compensation Expense	$ 504,000	219,000
2025 Plan [Member]
Employee Benefit Plans (Details) [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance (in Shares)			700,000
Share-Based Payment Arrangement, Option [Member]
Employee Benefit Plans (Details) [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period	4 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period	10 years
Employee Benefits and Share-Based Compensation	$ 357,000	487,000
Stock Appreciation Rights (SARs) [Member]
Employee Benefit Plans (Details) [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period	5 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in Shares)	20,000
Stock Appreciation Rights (SARs) [Member] \| Common Stock [Member]
Employee Benefit Plans (Details) [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in Shares)	4,556
Stock Appreciation Rights (SARs) [Member] \| Employees and Directors [Member]
Employee Benefit Plans (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Total Grants from Inception, Gross (in Shares)	2,385,000
Restricted Stock Units (RSUs) [Member]
Employee Benefit Plans (Details) [Line Items]
Share-Based Payment Arrangement, Noncash Expense	$ 776,000	301,000
Performance Shares [Member]
Employee Benefit Plans (Details) [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period	4 years
UNITED STATES \| Fair Value, Inputs, Level 1 [Member]
Employee Benefit Plans (Details) [Line Items]
Assets, Fair Value Disclosure	$ 3,500,000	2,800,000
UNITED STATES \| Fair Value, Inputs, Level 2 [Member]
Employee Benefit Plans (Details) [Line Items]
Assets, Fair Value Disclosure	$ 400,000	$ 900,000