CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 114	$ 141
Preferred stock - par value (in dollars per share)	$ 1.00	$ 1.00
Preferred stock - shares authorized (in shares)	960,000	960,000
Preferred stock - outstanding (in shares)	0	0
Common stock - par value (in dollars per share)	$ 0.10	$ 0.10
Common stock - shares authorized (in shares)	7,500,000	7,500,000
Common stock - shares outstanding (in shares)	4,243,716	4,235,533
Operating lease right-of-use assets, net	$ 8,051	$ 9,576
Operating lease liabilities	2,050	2,252
Operating lease liabilities	$ 6,000	$ 7,323