Nature of Business and Summary of Significant Accounting Policies (Narrative) (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016	Jun. 30, 2016
Significant Accounting Policies [Line Items]
Carrying amount of long-term debt, including current portion	$ 3,500,000		$ 3,500,000
Short-term time deposits	461,000		461,000
Intangible assets amortization expense	111,000	$ 131,000	331,000	$ 398,000
Estimated amortization expense-2017	441,000		441,000
Estimated amortization expense-2018	371,000		371,000
Estimated amortization expense-2019	313,000		313,000
Estimated amortization expense-2020	264,000		264,000
Estimated amortization expense-2021	$ 223,000		$ 223,000
Weighted average amortization period for acquired intangible assets			11 years 3 months 18 days	12 years 3 months 18 days
Antidilutive options outstanding excluded from diluted EPS computations	0	166,000	0	147,000
Stock-based compensation costs	$ 0	$ 0	$ 97,000	$ 92,000
Sales Returns And Allowances Percentage			8.00%	7.00%
Stock-based compensation costs, effect on EPS	$ 0.00	$ 0.00	$ 00	$ 0.00
Selling, General and Administrative Expenses [Member]
Significant Accounting Policies [Line Items]
Advertising and promotion costs	$ 365,000	$ 259,000	$ 1,537,000	$ 1,328,000
Sales revenue, net [Member]
Significant Accounting Policies [Line Items]
Shipping and handling revenue	250,000	232,000	683,000	673,000
Cost of sales [Member]
Significant Accounting Policies [Line Items]
Research and development costs	1,698,000	1,513,000	4,935,000	4,521,000
Shipping and handling expense	104,000	$ 109,000	349,000	$ 365,000
Allowance for doubtful accounts current [Member]
Significant Accounting Policies [Line Items]
Valuation allowances and reserves, balance	145,000		145,000		$ 145,000
Returns and other allowances [Member]
Significant Accounting Policies [Line Items]
Valuation allowances and reserves, balance	$ 1,280,000		$ 1,280,000		$ 1,255,000