Statements of Cash Flows - USD ($)	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Cash Flows from Operating Activities:
Net income	$ 1,163,668	$ 2,342,694
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Bad debt expense		69,010
Stock-based compensation	189,639	172,148
Depreciation	568,528	540,978
ESOP compensation expense	305,006	390,369
Loss on disposal of assets	4,525	566
Deferred income tax (benefit) expense	(43,641)	258,040
Changes in assets and liabilities:
Decrease (increase) in trade receivables	1,982,378	(6,687,067)
Decrease in income tax receivable		161,975
Increase in inventories	(1,562,918)	(1,816,211)
Decrease in prepaid expenses and other current assets	97,295	798,394
Increase in accounts payable	701,263	337,836
Increase (decrease) in accrued salaries and wages	139,311	(199,115)
(Decrease) increase in vacation accrual	(97,036)	79,258
Increase in other accrued expenses	208,567	5,092
Increase in payroll and other taxes withheld	125,519	8,016
Increase (decrease) in contract liabilities	2,169,181	(96,870)
Increase in income taxes payable	17,226	30,481
Net cash provided by (used in) operating activities	5,968,511	(3,604,406)
Cash Flows from Investing Activities:
Additions to property, plant and equipment	(214,421)	(608,318)
Purchase of investment securities	(9,338,100)	(6,039,808)
Proceeds from sale/maturity of investment securities	9,878,531	11,882,666
Net cash provided by investing activities	326,010	5,234,540
Cash Flows from Financing Activities:
Dividends paid on common stock	(2,388,211)	(4,736,962)
Purchase of treasury stock	(47,949)	(44,888)
Proceeds from exercise of stock options	81,000	315,681
Net cash used in financing activities	(2,355,160)	(4,466,169)
Increase (decrease) in cash and cash equivalents	3,939,361	(2,836,035)
Cash and cash equivalents, beginning of the year	1,462,761	4,298,796
Cash and cash equivalents, end of the year	5,402,122	1,462,761
Supplemental Schedule of Cash Flow Information:
Income taxes paid	$ 172,475	$ 87,200