Shareholders' Equity - Summary of common shareholders' equity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Shareholders' Equity
Beginning balance	$ 24,494	$ 35,112
Retirement benefits adjustment	19	13
Stock based compensation	63	41
Net Income (Loss)	(383)	(1,547)
Ending balance	24,193	33,619
Common Stock
Shareholders' Equity
Beginning balance	525	523
Retirement benefits adjustment	0	0
Stock based compensation	0	0
Net Income (Loss)	0	0
Ending balance	525	523
Capital in excess of par value
Shareholders' Equity
Beginning balance	14,617	14,556
Retirement benefits adjustment	0	0
Stock based compensation	44	17
Net Income (Loss)	0	0
Ending balance	14,661	14,573
Retained earnings
Shareholders' Equity
Beginning balance	12,954	23,741
Retirement benefits adjustment	0	0
Stock based compensation	0	0
Net Income (Loss)	(383)	(1,547)
Ending balance	12,571	22,194
Accumulated Other Comprehensive Loss
Shareholders' Equity
Beginning balance	(2,389)	(2,337)
Retirement benefits adjustment	19	13
Stock based compensation	0	0
Net Income (Loss)	0	0
Ending balance	(2,370)	(2,324)
ESOT
Shareholders' Equity
Beginning balance	(56)	(157)
Retirement benefits adjustment	0	0
Stock based compensation	0	0
Net Income (Loss)	0	0
Ending balance	(56)	(157)
Treasury stock
Shareholders' Equity
Beginning balance	(1,157)	(1,214)
Retirement benefits adjustment	0	0
Stock based compensation	19	24
Net Income (Loss)	0	0
Ending balance	$ (1,138)	$ (1,190)