Condensed Consolidated Statements of Stockholders' Equity (unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid - In Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
BALANCE at beginning of year at Dec. 31, 2019	$ 73,350	$ 19	$ 133,954	$ (60,305)	$ (318)
Stock-based compensation expense	1,563	1	1,562	0	0
Issuance of shares for stock purchase plans and stock options	496	0	496	0	0
Cancellation of shares for payment of withholding tax	(1,106)	0	(1,106)	0	0
Repurchase of common stock	(2,000)	(1)	(1,999)	0	0
Dividends paid	(2,054)	0	(2,054)	0	0
Net (loss) income	504	0	0	504	0
Change in cumulative translation adjustment, net	(74)	0	0	0	(74)
BALANCE at end of year at Jun. 30, 2020	70,679	19	130,853	(59,801)	(392)
BALANCE at beginning of year at Mar. 31, 2020	69,056	18	130,438	(60,993)	(407)
Stock-based compensation expense	1,001	1	1,000	0	0
Issuance of shares for stock purchase plans and stock options	437	0	437	0	0
Dividends paid	(1,022)	0	(1,022)	0	0
Net (loss) income	1,192	0	0	1,192	0
Change in cumulative translation adjustment, net	15	0	0	0	15
BALANCE at end of year at Jun. 30, 2020	70,679	19	130,853	(59,801)	(392)
BALANCE at beginning of year at Dec. 31, 2020	71,398	18	128,250	(56,888)	18
Stock-based compensation expense	1,657	1	1,656	0	0
Issuance of shares for stock purchase plans and stock options	418	0	418	0	0
Cancellation of shares for payment of withholding tax	(782)	0	(782)	0	0
Repurchase of common stock	(733)	0	(733)	0	0
Dividends paid	(2,018)	0	(2,018)	0	0
Net (loss) income	(831)	0	0	(831)	0
Change in cumulative translation adjustment, net	(86)	0	0	0	(86)
BALANCE at end of year at Jun. 30, 2021	69,023	19	126,791	(57,719)	(68)
BALANCE at beginning of year at Mar. 31, 2021	69,645	19	127,174	(57,550)	2
Stock-based compensation expense	1,039	0	1,039	0	0
Issuance of shares for stock purchase plans and stock options	410	0	410	0	0
Cancellation of shares for payment of withholding tax	(123)	0	(123)	0	0
Repurchase of common stock	(702)	0	(702)	0	0
Dividends paid	(1,007)	0	(1,007)	0	0
Net (loss) income	(169)	0	0	(169)	0
Change in cumulative translation adjustment, net	(70)	0	0	0	(70)
BALANCE at end of year at Jun. 30, 2021	$ 69,023	$ 19	$ 126,791	$ (57,719)	$ (68)