Nature of Business and Summary of Significant Accounting Policies (Narrative) (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2016
Significant Accounting Policies [Line Items]
Carrying amount of long-term debt, including current portion	$ 2,350,000		$ 2,350,000
Short-term time deposits	460,000		460,000		$ 460,000
Intangible assets amortization expense	110,000	$ 131,000	220,000	$ 268,000
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 7 months 6 days	12 years 7 months 6 days
Antidilutive options outstanding excluded from diluted EPS computations	5,000	106,000	5,000	137,750
Stock-based compensation costs	$ 65,000	$ 60,000	$ 98,000	$ 92,000
Sales Returns And Allowances Percentage			8.00%	7.00%
Stock-based compensation costs, effect on EPS	$ 00	$ 00	$ 0.01	$ 00
Selling, General and Administrative Expenses [Member]
Significant Accounting Policies [Line Items]
Advertising and promotion costs	$ 498,000	$ 510,000	$ 1,172,000	$ 1,068,000
Sales revenue, net [Member]
Significant Accounting Policies [Line Items]
Shipping and handling revenue	217,000	225,000	433,000	441,000
Cost of sales [Member]
Significant Accounting Policies [Line Items]
Research and development costs	1,609,000	1,519,000	3,237,000	3,008,000
Shipping and handling expense	105,000	$ 125,000	245,000	$ 256,000
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	$ 1,199,000		$ 1,199,000		$ 1,255,000