Note 6 - Debt - Schedule of Debt (Details) (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2023	Apr. 30, 2022
Notes Collateralized by BHCMC's Assets and Compensation Due under State Management Contract Due December 2027 [Member]
Interest rate	5.32%	5.32%
Maturity date	Dec. 31, 2027	Dec. 31, 2027
Balloon payment	$ 19,250	$ 19,250
Note Collateralized By All Of BHCMC's Assets and Compensation due under the State Management Contract Due October 2026 [Member]
Interest rate	5.75%	5.75%
Maturity date	Oct. 31, 2026	Oct. 31, 2026
Note Collateralized by Equipment Due April 2022 [Member]
Interest rate	6.25%	6.25%
Note Collateralized by Real Estate [Member]
Interest rate	6.25%	6.25%
Note Collateralized by Real Estate Due March 2029 [Member]
Maturity date	Mar. 31, 2029	Mar. 31, 2029
Balloon payment	$ 652	$ 652
Note Collateralized by Real Estate Due March 2029 [Member] \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Basis spread	1.75%	1.75%
Note Two Collateralized by Real Estate Due March 2029 [Member]
Maturity date	Mar. 31, 2029	Mar. 31, 2029
Balloon payment	$ 702	$ 702
Note Two Collateralized by Real Estate Due March 2029 [Member] \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Basis spread	1.75%	1.75%
Note Collateralized by Aircraft Security Agreement [Member]
Interest rate	4.35%	4.35%
Maturity date	Mar. 31, 2029	Mar. 31, 2029
Balloon payment	$ 358	$ 358
Note Collateralized by Equipment Due October 2025 [Member]
Interest rate	8.13%	8.13%
Maturity date	Oct. 31, 2025	Oct. 31, 2025
Balloon payment	$ 41	$ 41

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section S99
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-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

+ References

No definition available.

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