Nature of Business and Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Jun. 30, 2019
Significant Accounting Policies [Line Items]
Short-term time deposits	$ 460,000		$ 460,000		$ 460,000
Intangible assets amortization expense	66,000	$ 78,000	198,000	$ 235,000
Estimated amortization expense- 2020	264,000		264,000
Estimated amortization expense - 2021	223,000		223,000
Estimated amortization expense - 2022	188,000		188,000
Estimated amortization expense - 2023	159,000		159,000
Estimated amortization expense- 2024	134,000		$ 134,000
Remaining weighted average amortization period for acquired intangible assets			8 years 4 months 24 days		9 years 4 months 24 days
Research and development costs	$ 1,815,000	$ 1,851,000	$ 5,387,000	$ 5,358,000
Antidilutive options outstanding excluded from diluted EPS computations	0	0	27,000	3,942
Stock-based compensation costs	$ 172,000	$ 0	$ 497,000	$ 152,000
Foreign Currency Transaction Gain (Loss), before Tax			$ 0	$ 0
Stock-based compensation costs, effect on EPS	$ 0.02	$ 0.00	$ 0.04	$ 0.01
Number of Operating Segments			1
Cost of Goods and Services Sold	$ 14,283,000	$ 14,414,000	$ 42,752,000	$ 42,389,000
Selling, General and Administrative Expenses [Member]
Significant Accounting Policies [Line Items]
Advertising and promotion costs	307,000	190,000	1,448,000	1,278,000
Sales revenue, net [Member] | Shipping and Handling [Member]
Significant Accounting Policies [Line Items]
Cost of Goods and Services Sold	300,000	280,000	831,000	827,000
Cost of sales [Member]
Significant Accounting Policies [Line Items]
Research and development costs	1,816,000	1,851,000	5,387,000	5,358,000
Cost of sales [Member] | Shipping and Handling [Member]
Significant Accounting Policies [Line Items]
Cost of Goods and Services Sold	135,000	$ 109,000	355,000	$ 313,000
Allowance for doubtful accounts current [Member]
Significant Accounting Policies [Line Items]
Valuation allowances and reserves, balance	$ 326,000		$ 326,000		$ 88,000