Revenue from Contracts with Customers (Summary of Cumulative Effect of Changes to Unaudited Consolidated Statement of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Net Sales	$ 15,632	$ 21,397	$ 58,627	$ 61,099
Cost of Sales	10,485	13,475	37,338	38,120
Gross Profit	5,147	7,922	21,289	22,979
Operating Expenses
Selling, general and administrative	4,415	4,700	13,992	13,621
Engineering, research and development	1,812	2,132	6,090	5,662
Severance, impairment and other charges	0	(3)	(609)	603
Total operating expenses	6,227	6,829	19,473	19,886
Operating (Loss) Income	(1,080)	1,093	1,816	3,093
Other Income and (Expenses)
Interest expense, net	(16)	(53)	(72)	(137)
Foreign currency (loss) gain, net	(127)	63	(178)	(16)
Other income (expenses), net	28	24	33	49
Total other (expense) and income	(115)	34	(217)	(104)
(Loss) Income Before Income Taxes	(1,195)	1,127	1,599	2,989
Income Tax Benefit	130	(107)	(225)	(45)
Net (Loss) Income	(1,065)	$ 1,020	1,374	$ 2,944
ASC 606 Adjustments [Member] | ASC 606 [Member]
Net Sales	(3,254)		(5,831)
Cost of Sales	(1,463)		(2,784)
Gross Profit	(1,791)		(3,047)
Operating Expenses
Selling, general and administrative	2		202
Total operating expenses	2		202
Operating (Loss) Income	(1,793)		(3,249)
Other Income and (Expenses)
(Loss) Income Before Income Taxes	(1,793)		(3,249)
Income Tax Benefit	381		830
Net (Loss) Income	(1,412)		(2,419)
Balances Without Adoption of ASC 606 [Member] | ASC 606 [Member]
Net Sales	12,378		52,796
Cost of Sales	9,022		34,554
Gross Profit	3,356		18,242
Operating Expenses
Selling, general and administrative	4,417		14,194
Engineering, research and development	1,812		6,090
Severance, impairment and other charges			(609)
Total operating expenses	6,229		19,675
Operating (Loss) Income	(2,873)		(1,433)
Other Income and (Expenses)
Interest expense, net	(16)		(72)
Foreign currency (loss) gain, net	(127)		(178)
Other income (expenses), net	28		33
Total other (expense) and income	(115)		(217)
(Loss) Income Before Income Taxes	(2,988)		(1,650)
Income Tax Benefit	511		605
Net (Loss) Income	$ (2,477)		$ (1,045)