STATEMENTS OF SHAREHOLDERS' EQUITY (Unaudited) - USD ($)	Common Stock	Additional Paid-in Capital	AOCI Including Portion Attributable to Noncontrolling Interest	Retained Earnings	Total
Equity Balance, Starting at Mar. 31, 2023	$ 48,308	$ 19,295,442	$ (1,213,858)	$ 48,949,610	$ 67,079,502
Shares Outstanding, Starting at Mar. 31, 2023	4,830,826
Unrealized loss from marketable securities, net of tax			(234,701)		(234,701)
Net income				4,403,730	4,403,730
Total comprehensive income					4,169,029
Shares Granted, Value, Share-Based Payment Arrangement, after Forfeiture		10,536			10,536
Dividends, Cash				(4,830,826)	(4,830,826)
Stock Issued During Period, Value, Stock Options Exercised	$ 26	117,501			117,527
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period	2,575
Shares Outstanding, Ending at Jun. 30, 2023	4,833,401
Equity Balance, Ending at Jun. 30, 2023	$ 48,334	19,423,479	(1,448,559)	48,522,514	66,545,768
Equity Balance, Starting at Mar. 31, 2023	$ 48,308	19,295,442	(1,213,858)	48,949,610	67,079,502
Shares Outstanding, Starting at Mar. 31, 2023	4,830,826
Unrealized loss from marketable securities, net of tax					460,541
Net income					13,311,718
Total comprehensive income					$ 13,772,259
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period					4,000
Shares Outstanding, Ending at Dec. 31, 2023	4,833,401
Equity Balance, Ending at Dec. 31, 2023	$ 48,334	19,542,335	(753,317)	47,763,700	$ 66,601,052
Equity Balance, Starting at Jun. 30, 2023	$ 48,334	19,423,479	(1,448,559)	48,522,514	66,545,768
Shares Outstanding, Starting at Jun. 30, 2023	4,833,401
Unrealized loss from marketable securities, net of tax			(53,588)		(53,588)
Net income				4,723,566	4,723,566
Total comprehensive income					4,669,978
Shares Granted, Value, Share-Based Payment Arrangement, after Forfeiture		106,312			106,312
Dividends, Cash				(4,833,401)	(4,833,401)
Shares Outstanding, Ending at Sep. 30, 2023	4,833,401
Equity Balance, Ending at Sep. 30, 2023	$ 48,334	19,529,791	(1,502,147)	48,412,679	66,488,657
Unrealized loss from marketable securities, net of tax			748,830		748,830
Net income				4,184,422	4,184,422
Total comprehensive income					4,933,252
Shares Granted, Value, Share-Based Payment Arrangement, after Forfeiture		12,544			12,544
Dividends, Cash				(4,833,401)	$ (4,833,401)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period					0
Shares Outstanding, Ending at Dec. 31, 2023	4,833,401
Equity Balance, Ending at Dec. 31, 2023	$ 48,334	19,542,335	(753,317)	47,763,700	$ 66,601,052
Equity Balance, Starting at Mar. 31, 2024	$ 48,337	19,554,812	(777,637)	46,743,005	65,568,517
Shares Outstanding, Starting at Mar. 31, 2024	4,833,676
Unrealized loss from marketable securities, net of tax			28,710		28,710
Net income				4,097,587	4,097,587
Total comprehensive income					4,126,297
Shares Granted, Value, Share-Based Payment Arrangement, after Forfeiture		18,442			18,442
Dividends, Cash				(4,833,676)	(4,833,676)
Shares Outstanding, Ending at Jun. 30, 2024	4,833,676
Equity Balance, Ending at Jun. 30, 2024	$ 48,337	19,573,254	(748,927)	46,006,916	64,879,580
Equity Balance, Starting at Mar. 31, 2024	$ 48,337	19,554,812	(777,637)	46,743,005	65,568,517
Shares Outstanding, Starting at Mar. 31, 2024	4,833,676
Unrealized loss from marketable securities, net of tax					482,279
Net income					11,172,142
Total comprehensive income					$ 11,654,421
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period					9,000
Shares Outstanding, Ending at Dec. 31, 2024	4,837,166
Equity Balance, Ending at Dec. 31, 2024	$ 48,372	19,806,845	(295,358)	43,412,629	$ 62,972,488
Equity Balance, Starting at Jun. 30, 2024	$ 48,337	19,573,254	(748,927)	46,006,916	64,879,580
Shares Outstanding, Starting at Jun. 30, 2024	4,833,676
Unrealized loss from marketable securities, net of tax			680,417		680,417
Net income				4,026,145	4,026,145
Total comprehensive income					4,706,562
Shares Granted, Value, Share-Based Payment Arrangement, after Forfeiture		105,203			105,203
Dividends, Cash				(4,833,676)	(4,833,676)
Stock Issued During Period, Value, Stock Options Exercised	$ 3	(32)			(29)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period	344
Shares Outstanding, Ending at Sep. 30, 2024	4,834,020
Equity Balance, Ending at Sep. 30, 2024	$ 48,340	19,678,425	(68,510)	45,199,385	64,857,640
Unrealized loss from marketable securities, net of tax			(226,848)		(226,848)
Net income				3,048,410	3,048,410
Total comprehensive income					2,821,562
Shares Granted, Value, Share-Based Payment Arrangement, after Forfeiture		14,261			14,261
Dividends, Cash				(4,835,166)	(4,835,166)
Stock Issued During Period, Value, Stock Options Exercised	$ 32	114,159			$ 114,191
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period	3,146				8,000
Shares Outstanding, Ending at Dec. 31, 2024	4,837,166
Equity Balance, Ending at Dec. 31, 2024	$ 48,372	$ 19,806,845	$ (295,358)	$ 43,412,629	$ 62,972,488