Summary of Significant Accounting Policies - Basic and diluted earnings per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
Numerator:
Net income (loss)	$ 2,729	$ 3,350	$ 920	$ (104)	$ 3,823	$ 1,204	$ 6,999	$ 4,923
Less: Income allocated to unvested participating securities	41			(1)			105	37
Net income available to common shareholders	$ 2,688			$ (103)			$ 6,894	$ 4,886
Denominator:
Denominator for basic earnings per share - weighted average shares	6,032			5,961			6,031	5,977
Effect of dilutive securities:
Common stock equivalents	0			0			0	0
Denominator for diluted earnings per share - adjusted weighted-average shares and assumed conversions	6,032			5,961			6,031	5,977
Basic earnings (loss) per share:
Basic (Dollars per share)	$ 0.45			$ (0.01)			$ 1.15	$ 0.82
Diluted earnings (loss) per share:
Diluted (Dollars per share)	$ 0.45			$ (0.01)			$ 1.15	$ 0.82