Summary of Significant Accounting Policies - Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earnings (losses) from continuing operations									$ 2,945	$ (482)	$ 3,943
Losses from investment in unconsolidated affiliate, net of tax									0	0	(1,430)
Net (losses) earnings	$ (3,848)	$ 2,035	$ 3,620	$ 1,138	$ 3,693	$ (3,033)	$ (282)	$ (860)	$ 2,945	$ (482)	$ 2,513
Basic weighted average number of shares outstanding (in shares)									4,218	4,218	4,218
Basic earnings (losses) per share:
From continuing operations (in dollars per share)									$ 0.70	$ (0.11)	$ 0.94
From investment in unconsolidated affiliate (in dollars per share)									0	0	(0.34)
Basic net (losses) earnings per common share (in dollars per share)	$ (0.91)	$ 0.48	$ 0.86	$ 0.27					$ 0.70	$ (0.11)	$ 0.60
Diluted earnings (losses) per share:
Diluted weighted average number of shares outstanding (in shares)									4,218	4,218	4,218
From continuing operations (in dollars per share)									$ 0.70	$ (0.11)	$ 0.94
From investment in unconsolidated affiliate (in dollars per share)									0	0	(0.34)
Diluted earnings (losses) per share (in dollars per share)	$ (0.91)	$ 0.48	$ 0.86	$ 0.27					$ 0.70	$ (0.11)	$ 0.60
Restricted stock units awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units award									0	0	0
Performance share unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units award									0	0	0