STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
OPERATING ACTIVITIES
Net income	$ 15,199,195	$ 15,064,516
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation	460,028	324,232
Bond discount amortization	(317,811)	(307,666)
Stock-based compensation	93,663	152,167
Deferred income taxes	2,105,121	(611,969)
Non-cash operating lease expense (credit)	107,863	(61,355)
Changes in operating assets and liabilities
Accounts receivable	180,327	(444,435)
Inventories	366,262	(290,498)
Prepaid expenses and other assets	(1,427,001)	255,935
Accounts payable	63,908	87,537
Accrued payroll and other	(173,558)	141,954
Net cash provided by operating activities	16,657,997	14,310,418
INVESTING ACTIVITIES
Purchases of marketable securities	(15,242,719)	(11,279,773)
Proceeds from maturities of marketable securities	13,800,000	15,205,000
Purchases of fixed assets	(2,189,138)	(1,257,109)
Net cash (used in) provided by investing activities	(3,631,857)	2,668,118
FINANCING ACTIVITIES
Payment of dividends to shareholders	(19,348,664)	(19,339,684)
Net proceeds from exercise of stock options	0	114,162
Net cash used in financing activities	(19,348,664)	(19,225,522)
Decrease in cash and cash equivalents	(6,322,524)	(2,246,986)
Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation, Beginning Balance	8,036,564	10,283,550
Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation, Ending Balance	1,714,040	8,036,564
Supplemental disclosures of cash flow information
Cash paid during the year for income taxes	$ 1,933,149	$ 3,311,534