Nature of Business and Summary of Significant Accounting Policies (Narrative) (Detail) - USD ($)	3 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018
Significant Accounting Policies [Line Items]
Short-term time deposits	$ 460,000		$ 460,000
Intangible assets amortization expense	78,000	$ 93,000
Estimated amortization expense-2019	313,000
Estimated amortization expense-2020	264,000
Estimated amortization expense-2021	223,000
Estimated amortization expense-2022	188,000
Estimated amortization expense-2023	$ 159,000
Weighted average amortization period for acquired intangible assets	9 years 10 months 24 days	10 years 10 months 24 days
Research and development costs	$ 1,745,000	$ 1,607,000
Stock-based compensation costs	$ 5,000	$ 33,000
Stock-based compensation costs, effect on EPS	$ 0.00	$ 0.00
Cost of Goods and Services Sold	$ 13,817,000	$ 12,688,000
Customer Relationships [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years
Selling, General and Administrative Expenses [Member]
Significant Accounting Policies [Line Items]
Advertising and promotion costs	$ 650,000	641,000
Sales revenue, net [Member] | Shipping and Handling [Member]
Significant Accounting Policies [Line Items]
Cost of Goods and Services Sold	282,000	207,000
Cost of sales [Member]
Significant Accounting Policies [Line Items]
Research and development costs	1,745,000	1,607,000
Cost of sales [Member] | Shipping and Handling [Member]
Significant Accounting Policies [Line Items]
Cost of Goods and Services Sold	101,000	$ 122,000
Allowance for doubtful accounts current [Member]
Significant Accounting Policies [Line Items]
Valuation allowances and reserves, balance	$ 189,000		$ 195,000