Stock-Based Compensation - Schedule of SAR Activity (Details) - SARs - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Shares
Outstanding, beginning balance (in shares)	83,720	152,600
Granted (in shares)	60,000	5,000
Exercised (in shares)	0	0
Forfeited (in shares)	(1,000)	(67,130)
Expired (in shares)	(4,700)	(6,750)
Outstanding, ending balance (in shares)	138,020	83,720	152,600
Exercisable (in shares)	87,370	39,360
Weighted-Average Exercise Price
Outstanding, beginning balance (in dollars per share)	$ 11.02	$ 16.55
Granted (in dollars per share)	7.92	7.37
Exercised (in dollars per share)	0.00	0.00
Forfeited (in dollars per share)	11.25	23.16
Expired (in dollars per share)	11.25	12.68
Outstanding, ending balance (in dollars per share)	9.66	11.02	$ 16.55
Exercisable (in dollars per share)	$ 11.14	$ 11.25
Weighted-Average Remaining Contractual Term (years)
Outstanding (term)	8 years 20 days	8 years 2 months 16 days	9 years 7 days
Exercisable (term)	6 years 2 months 15 days	8 years 1 month 24 days
Aggregate Intrinsic Value (in thousands)
Outstanding	$ 89	$ 1
Exercisable	$ 5	$ 0