STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($)	Common Stock	Additional Paid-in Capital	AOCI Including Portion Attributable to Noncontrolling Interest	Retained Earnings	Total
Equity Balance, Starting at Mar. 31, 2022	$ 48,308	$ 19,256,485	$ (318,120)	$ 45,578,456	$ 64,565,129
Shares Outstanding, Starting at Mar. 31, 2022	4,830,826
Repurchase of common stock	$ (3)	(20,697)			(20,700)
Repurchase of common stock	(264)
Stock Issued During Period, Value, Stock Options Exercised	$ 3	(3)			$ 0
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period	264				1,000
Unrealized gain (loss) from marketable securities, net of tax			(895,738)		$ (895,738)
Net income				22,694,458	22,694,458
Total comprehensive income					21,798,720
Shares Granted, Value, Share-Based Payment Arrangement, after Forfeiture		59,657			59,657
Cash dividends declared ($4.00 per share of common stock)				(19,323,304)	(19,323,304)
Shares Outstanding, Ending at Mar. 31, 2023	4,830,826
Equity Balance, Ending at Mar. 31, 2023	$ 48,308	19,295,442	(1,213,858)	48,949,610	67,079,502
Stock Issued During Period, Value, Stock Options Exercised	$ 29	117,434			$ 117,463
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period	2,850				5,000
Unrealized gain (loss) from marketable securities, net of tax			436,221		$ 436,221
Net income				17,124,699	17,124,699
Total comprehensive income					17,560,920
Shares Granted, Value, Share-Based Payment Arrangement, after Forfeiture		141,936			141,936
Cash dividends declared ($4.00 per share of common stock)				(19,331,304)	(19,331,304)
Shares Outstanding, Ending at Mar. 31, 2024	4,833,676
Equity Balance, Ending at Mar. 31, 2024	$ 48,337	$ 19,554,812	$ (777,637)	$ 46,743,005	$ 65,568,517