7. Stockholders' Equity (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Common Stock
Beginning balance, shares	13,929,381	13,929,381	13,883,937	13,882,937	13,929,381	13,882,937
Beginning balance, amount	$ 8,357	$ 8,357	$ 8,330	$ 8,330	$ 8,357	$ 8,330
Common stock issued under restricted stock units, shares	14,439		38,353
Common stock issued under restricted stock units, amount	$ 9		$ 23
Stock options exercised and issued, shares				1,000
Ending balance, shares	13,943,820	13,929,381	13,922,290	13,883,937	13,943,820	13,922,290
Ending balance, amount	$ 8,366	$ 8,357	$ 8,353	$ 8,330	$ 8,366	$ 8,353
Additional Paid-In Capital
Beginning balance, amount	26,095	26,095	25,941	25,867	26,095	25,867
Common stock issued under restricted stock units, amount	(9)		(23)
Stock options exercised and issued, amount				2
Share-based compensation expense-stock options	30	30	37	31
Share-based compensation expense-restricted stock units	68	21	33	41
Ending balance, amount	26,235	26,095	25,988	25,941	26,235	25,988
Accumulated Deficit
Beginning balance, amount	(6,043)	(6,043)	(3,965)	(2,393)	(6,043)	(2,393)
Dividends declared ($0.02 per share)	(252)	(250)	(255)	(254)
Net loss	(302)	(1,192)	(247)	(1,318)
Ending balance, amount	(8,039)	(6,043)	(4,467)	(3,965)	(8,039)	(4,467)
Treasury Stock
Beginning balance, amount	(5,133)	(5,133)	(4,429)	(4,092)	(5,133)	(4,092)
Repurchase of common stock	(26)	(243)	(213)	(337)
Ending balance, amount	(5,402)	(5,133)	(4,642)	(4,429)	(5,402)	(4,642)
Beginning balance, amount	23,276	23,276	25,877	27,712	23,276	27,712
Common stock issued under restricted stock units, amount	0		0
Stock options exercised and issued, amount				2
Share-based compensation expense-stock options	30	30	37	31
Share-based compensation expense-restricted stock units	68	21	33	41	89	74
Dividends declared ($0.02 per share)	(252)	(250)	(255)	(254)
Net loss	(302)	(1,192)	(247)	(1,318)	(1,494)	(1,565)
Repurchase of common stock	(26)	(243)	(213)	(337)	(269)	(550)
Ending balance, amount	$ 21,160	$ 23,276	$ 25,232	$ 25,877	$ 21,160	$ 25,232