Revenue from Contracts with Customers (Summary of Cumulative Effect of Changes to Unaudited Consolidated Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Jul. 01, 2018	Jun. 30, 2018	Dec. 31, 2017
Current Assets
Cash and cash equivalents	$ 6,899		$ 5,830
Short-term investments	1,131		877
Receivables:
Billed receivables, net	28,753		31,797
Unbilled receivables, net	4,635	$ 1,864
Other receivables	284		346
Inventories, net	11,143		13,829
Other current assets	1,900		1,327
Total current assets	54,745		54,006
Property and Equipment, Net	6,785		6,613
Goodwill	7,859		7,985
Intangible Assets, Net	3,428		3,820
Long-Term Investments	725		725
Long-Term Deferred Income Tax Asset	1,100		1,055
Total Assets	74,642		74,204
Current Liabilities
Line of credit and short-term notes payable	69		175
Accounts payable	6,911		7,592
Accrued liabilities and expenses	4,177		4,256
Accrued compensation	1,940		3,155
Current portion of taxes payable	432		526
Income taxes payable	1,134		768
Reserves for restructuring and other charges	66		675
Deferred revenue	7,389	6,715	8,691
Total current liabilities	22,118		25,838
Long-Term Taxes Payable	250		450
Long-Term Deferred Income Tax Liability	1,718		1,717
Other Long-Term Liabilities	593		601
Total Liabilities	24,679		28,606
Shareholders' Equity
Preferred stock, no par value, authorized 1,000 shares, issued none	0		0
Common stock	96		96
Accumulated other comprehensive loss	(2,864)		(2,098)
Additional paid-in capital	48,753		48,110
Retained earnings (deficit)	3,978		(510)
Total Shareholders' Equity	49,963		45,598	$ 43,814
Total Liabilities and Shareholders' Equity	74,642		74,204
ASC 606 [Member]
Receivables:
Unbilled receivables, net		1,864
Inventories, net		12,479
Other current assets		1,376
Current Liabilities
Deferred revenue		6,715
Long-Term Deferred Income Tax Liability		2,207
Shareholders' Equity
Retained earnings (deficit)		$ 1,539
ASC 606 Adjustments [Member] | ASC 606 [Member]
Receivables:
Unbilled receivables, net	(4,635)		1,864
Inventories, net	2,687		(1,350)
Other current assets	(249)		49
Total current assets	(2,197)
Total Assets	(2,197)
Current Liabilities
Deferred revenue	1,679		(1,976)
Total current liabilities	1,679
Long-Term Deferred Income Tax Liability	(939)		490
Total Liabilities	740
Shareholders' Equity
Preferred stock, no par value, authorized 1,000 shares, issued none
Accumulated other comprehensive loss	119
Retained earnings (deficit)	(3,056)		$ 2,049
Total Shareholders' Equity	(2,937)
Total Liabilities and Shareholders' Equity	(2,197)
Balances Without Adoption of ASC 606 [Member] | ASC 606 [Member]
Current Assets
Cash and cash equivalents	6,899
Short-term investments	1,131
Receivables:
Billed receivables, net	28,753
Other receivables	284
Inventories, net	13,830
Other current assets	1,651
Total current assets	52,548
Property and Equipment, Net	6,785
Goodwill	7,859
Intangible Assets, Net	3,428
Long-Term Investments	725
Long-Term Deferred Income Tax Asset	1,100
Total Assets	72,445
Current Liabilities
Line of credit and short-term notes payable	69
Accounts payable	6,911
Accrued liabilities and expenses	4,177
Accrued compensation	1,940
Current portion of taxes payable	432
Income taxes payable	1,134
Reserves for restructuring and other charges	66
Deferred revenue	9,068
Total current liabilities	23,797
Long-Term Taxes Payable	250
Long-Term Deferred Income Tax Liability	779
Other Long-Term Liabilities	593
Total Liabilities	25,419
Shareholders' Equity
Preferred stock, no par value, authorized 1,000 shares, issued none
Common stock	96
Accumulated other comprehensive loss	(2,745)
Additional paid-in capital	48,753
Retained earnings (deficit)	922
Total Shareholders' Equity	47,026
Total Liabilities and Shareholders' Equity	$ 72,445