Shareholders' Equity - Calculation of earning per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Shareholders' Equity
Net income	$ 541	$ 1,898
Weighted average common shares outstanding (basic) (in shares)	2,404	2,363
Unvested restricted stock (in shares)	3	27
Weighted average common shares outstanding (diluted) (in shares)	2,407	2,390
Basic
Net income per share	$ 0.23	$ 0.80
Diluted
Net income per share	$ 0.22	$ 0.79