Revenue from Contracts with Customers (Summary of Cumulative Effect of Changes to Unaudited Consolidated Statement of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Net Sales	$ 21,553	$ 20,433	$ 42,995	$ 39,702
Cost of Sales	13,703	13,026	26,853	24,645
Gross Profit	7,850	7,407	16,142	15,057
Operating Expenses
Selling, general and administrative	4,942	4,497	9,577	8,921
Engineering, research and development	2,080	1,797	4,278	3,530
Severance, impairment and other charges	(609)	658	(609)	606
Total operating expenses	6,413	6,952	13,246	13,057
Operating Income	1,437	455	2,896	2,000
Other Income and (Expenses)
Interest expense, net	(29)	(42)	(56)	(84)
Foreign currency gain (loss), net	151	(57)	(51)	(79)
Other income (expenses), net	5	(5)	5	25
Total other income and (expenses)	127	(104)	(102)	(138)
Income Before Income Taxes	1,564	351	2,794	1,862
Income Tax (Expense) Benefit	(17)	15	(355)	62
Net Income	1,547	$ 366	2,439	$ 1,924
ASC 606 Adjustments [Member] | ASC 606 [Member]
Net Sales	(273)		(2,577)
Cost of Sales	(173)		(1,321)
Gross Profit	(100)		(1,256)
Operating Expenses
Selling, general and administrative	16		200
Total operating expenses	16		200
Operating Income	(116)		(1,456)
Other Income and (Expenses)
Income Before Income Taxes	(116)		(1,456)
Income Tax (Expense) Benefit	172		449
Net Income	56		(1,007)
Balances Without Adoption of ASC 606 [Member] | ASC 606 [Member]
Net Sales	21,280		40,418
Cost of Sales	13,530		25,532
Gross Profit	7,750		14,886
Operating Expenses
Selling, general and administrative	4,958		9,777
Engineering, research and development	2,080		4,278
Severance, impairment and other charges	(609)		(609)
Total operating expenses	6,429		13,446
Operating Income	1,321		1,440
Other Income and (Expenses)
Interest expense, net	(29)		(56)
Foreign currency gain (loss), net	151		(51)
Other income (expenses), net	5		5
Total other income and (expenses)	127		(102)
Income Before Income Taxes	1,448		1,338
Income Tax (Expense) Benefit	155		94
Net Income	$ 1,603		$ 1,432