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Stock Options (Narrative) (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share Based Compensation Expense	$ 103,000	$ 65,000	$ 136,000	$ 98,000
Share based Compensation Cost Effect On Earnings Per Share Basic And Diluted	$ 0.00	$ 0.00	$ 0.00	$ 0.00
Proceeds From Stock Options Exercised			$ 16,000	$ 49,000
2012 Employee Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance under the plan	950,000		950,000
Percentage Applied To Market Price To Set Grant Price For Grantee Owning Ten Percent Or More Of Entity Common Stock Outstanding			110.00%
Term of stock option awards			10 years
Annual rate at which share-based compensation awards vest			20.00%
Number of stock options, exercisable	60,300	74,500	60,300	74,500
Number of stock options available for grant	823,900		823,900
Unearned stock-based compensation cost related to non-vested awards	$ 132,000		$ 132,000
Fair value of stock options that vested during the period	80,000	$ 59,000	96,000	$ 75,000
Tax benefit from ISO option exercise	$ 0	$ 0	$ 0	$ 0
Number of shares outstanding, end of period	88,100	115,600	88,100	115,600	70,600	112,500
Stock Issued During Period, Shares, New Issues	500	1,500	2,500	1,500
Common Stock, Voting Rights			Any plan participant who is granted ISOs and possesses more than 10% of the voting rights of the Company's outstanding common stock
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	20,000	5,000	20,000	5,000
Stock Issued During Period, Value, New Issues			$ 16,000	$ 9,000
2012 Non-Employee Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance under the plan	50,000		50,000
Term of stock option awards			10 years
Annual rate at which share-based compensation awards vest			20.00%
Number of stock options, exercisable	15,200	20,800	15,200	20,800
Unearned stock-based compensation cost related to non-vested awards	$ 72,000		$ 72,000
Fair value of stock options that vested during the period	$ 22,000	$ 6,000	39,000	$ 22,000
Tax benefit from ISO option exercise		$ 0	$ 0	$ 0
Number of shares outstanding, end of period	29,200	29,800	29,200	29,800	14,200	35,000
Stock Issued During Period, Shares, New Issues		5,200		5,200
Conversion of Stock, Shares Issued			3,056
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			15,000	0
2002 Employee Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance under the plan	1,836,000		1,836,000
Percentage Applied To Market Price To Set Grant Price For Grantee Owning Ten Percent Or More Of Entity Common Stock Outstanding			110.00%
Term of stock option awards			10 years
Annual rate at which share-based compensation awards vest			20.00%
Tax benefit from ISO option exercise	$ 0	$ 0	$ 0	$ 0
Number of shares outstanding, end of period	1,471,480		1,471,480
Remaining Stock Options Exercised	0	6,500	5,000	6,500
Conversion of Stock, Shares Issued			2,815	40,655
Common Stock, Voting Rights			Any plan participant who was granted ISOs and possessed more than 10% of the voting rights of the Company's outstanding common stock
Proceeds From Stock Options Exercised		$ 40,000		$ 40,000
Stock Issued During Period, Value, New Issues	$ 3,000	$ 9,000

X

- Definition

The sum of the market price plus the markup applied to market price on the date of grant to set the exercise price of a stock option awarded to a grantee owning 10% or more of the entity's outstanding common stock on the date of grant.

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Description of voting rights of common stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Gross number of share options (or share units) granted during the period.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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