Statements of Cash Flows - USD ($)	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash Flows from Operating Activities:
Net income	$ 2,342,694	$ 3,075,797
Adjustments to reconcile net income to net cash (used in) provided by operating activities:
Bad debt expense	69,010
Stock-based compensation	172,148	123,112
Depreciation	540,978	429,679
ESOP compensation expense	390,369	387,882
Loss on disposal of assets	566
Deferred income tax expense	258,040	115,075
Changes in assets and liabilities:
Increase in trade receivables, net	(6,687,067)	(978,113)
Decrease (increase) in income tax receivable	161,975	(41,796)
Increase in inventories, net	(1,816,211)	(363,611)
Decrease (increase) in prepaid expenses and other current assets	798,394	(1,065,269)
Increase (decrease) in accounts payable	337,836	(427,518)
(Decrease) increase in accrued salaries and wages	(199,115)	356,960
Increase in vacation accrual	79,258	51,413
Increase (decrease) in other accrued expenses	5,092	(145,620)
Increase in payroll and other taxes withheld	8,016	6,496
Decrease in contract liabilities	(96,870)	(1,263,580)
Increase in income taxes payable	30,481
Net cash (used in) provided by operating activities	(3,604,406)	260,907
Cash Flows from Investing Activities:
Additions to property, plant and equipment	(608,318)	(1,923,220)
Purchase of investment securities	(6,039,808)	(11,199,339)
Proceeds from sale/maturity of investment securities	11,882,666	9,102,457
Net cash provided by (used in) investing activities	5,234,540	(4,020,102)
Cash Flows from Financing Activities:
Dividends paid on common stock	(4,736,962)	(2,329,593)
Purchase of treasury stock	(44,888)	(109,694)
Proceeds from exercise of stock options	315,681	439,115
Net cash used in financing activities	(4,466,169)	(2,000,172)
Decrease in cash and cash equivalents	(2,836,035)	(5,759,367)
Cash and cash equivalents, beginning of the year	4,298,796	10,058,163
Cash and cash equivalents, end of the year	1,462,761	4,298,796
Supplemental Schedule of Cash Flow Information:
Income taxes paid	$ 87,200	$ 920,000