NOTE 6. STOCK-BASED COMPENSATION: Disclosure of Share-Based Compensation Arrangements by Share-Based Payment Award (Details) - $ / shares	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Details
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Beginning Balance	34,500	29,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Beginning Balance	$ 66.26	$ 69.52
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross	6,500	6,500
Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 79.29	$ 50.35
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period	(5,000)	(1,000)
Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 59.85	$ 57.46
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Ending Balance	36,000	34,500
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Ending Balance	$ 69.5	$ 66.26
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number	33,500	32,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 65.12	$ 63.6
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 22.15	$ 9.06

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(03)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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