Summary of Significant Accounting Policies, Deferred Compensation Plan (Details) - USD ($)	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Deferred Compensation Plan [Abstract]
Carrying value of plan assets	$ 1,837,000	$ 2,011,000
Deferred compensation obligation	1,837,000	2,011,000
Expense related to the deferred compensation plan	6,000	75,000	$ 119,000
Contributions made to deferred compensation plan	82,000	287,000	388,000
Short-term investments redeemed for the payment of deferred compensation liabilities	603,000	297,000	0
Gain (Loss) on Equity Investments [Abstract]
Net gain (loss) recognized on equity securities	347,000	(181,000)	163,000
Less: net gain (loss) recognized on equity securities sold	74,000	(15,000)	0
Unrealized gain (loss) recognized on equity securities still held	$ 273,000	$ (166,000)	$ 163,000

Amount of short-term investments redeemed during the reporting period.

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- Definition

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 710
-SubTopic 10
-Name Accounting Standards Codification
-Section 30
-Paragraph 1
-Publisher FASB
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Amount of contributions made by employer into fund established for purposes of making future disbursement to individual in accordance with deferred compensation arrangement.

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The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

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Amount of realized and unrealized gain (loss) on investment in marketable security.

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Amount of realized gain (loss) on investment in marketable security.

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Amount of unrealized gain (loss) on investment in marketable security.

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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

+ References

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