UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Contributed Capital	Retained Earnings
Beginning balance at Dec. 31, 2016	$ 151,312	$ 422	$ 11,693	$ 139,197
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (losses)	(1,142)			(1,142)
Dividends paid on common stock	(1,856)			(1,856)
Ending balance at Jun. 30, 2017	148,314	422	11,693	136,199
Beginning balance at Dec. 31, 2017	147,119	422	11,693	135,004
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (losses)	4,758			4,758
Stock-based compensation expense	3		3
Dividends paid on common stock	(1,856)			(1,856)
Ending balance at Jun. 30, 2018	$ 150,024	$ 422	$ 11,696	$ 137,906