Stockholders' Equity - Summary of common shareholders' equity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			$ 25,442
Balance (shares)			2,614,506
Net income	$ 366	$ 744	$ 1,628	$ 4,136
Purchase of treasury shares			(197)
Cash dividend			(380)
Stock based compensation, net of tax benefit			388
Balance	$ 26,881		$ 26,881
Balance (shares)	2,614,506		2,614,506
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			$ 523
Balance (shares)			2,614,506
Balance	$ 523		$ 523
Balance (shares)	2,614,506		2,614,506
Capital in excess of par value
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			$ 14,092
Stock based compensation, net of tax benefit			54
Balance	$ 14,146		14,146
Retained earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			13,395
Net income			1,628
Cash dividend			(380)
Balance	14,643		14,643
ESOT
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			(863)
Balance	(863)		(863)
Treasury stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			(1,702)
Purchase of treasury shares			(197)
Stock based compensation, net of tax benefit			334
Balance	(1,565)		(1,565)
Accumulated other comprehensive loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			(3)
Balance	$ (3)		$ (3)