Consolidated Statements of Changes in Stockholders’ Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Treasury Stock	Retained Earnings	Accumulated Other Comprehensive Loss
Balance at beginning of period at Dec. 31, 2016	$ 54,073	$ 2,818	$ 27,900	$ (2,114)	$ 29,960	$ (4,491)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	956				956
Other comprehensive income (loss)	258					258
Stock compensation expense	55		55
Dividends declared on common stock	(581)				(581)
Balance at end of period at Mar. 31, 2017	54,761	2,818	27,955	(2,114)	30,335	(4,233)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of change in accounting principle for marketable equity securities, net of tax						(187)
Cumulative effect of change in accounting principle for marketable equity securities, net of tax | Accounting Standards Update 2016-01	0				187	(187)
Balance at beginning of period (Previously Reported) at Dec. 31, 2017	59,091	2,966	31,031	(2,114)	32,726	(5,518)
Balance at beginning of period at Dec. 31, 2017	59,091	2,966	31,031	(2,114)	32,913	(5,705)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,362				1,362
Other comprehensive income (loss)	(1,015)					(1,015)
Stock compensation expense	75		75
Dividends declared on common stock	(636)				(636)
Balance at end of period at Mar. 31, 2018	$ 58,877	$ 2,966	$ 31,106	$ (2,114)	$ 33,639	$ (6,720)