Share-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Weighted Average Grant Date Fair Value [Abstract]
Stock-based compensation expense	$ 8	$ 0
Restricted Stock [Member]
Shares [Roll Forward]
Nonvested balance at beginning of period (in shares)	2,245
Issued (in shares)	0		0
Vested (in shares)	0
Forfeited (in shares)	0
Nonvested balance at end of period (in shares)	2,245		2,245
Weighted Average Grant Date Fair Value [Abstract]
Non-vested balance at beginning of period (in dollars per share)	$ 33.60
Issued (in dollars per share)	0
Vested (in dollars per share)	0
Forfeited (in dollars per share)	0
Non-vested balance at end of period (in dollars per share)	$ 33.60		$ 33.60
Weighted-average remaining vesting period for recognition	1 year 6 months
Unrecognized stock-based compensation expense	$ 50
2016 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)	300,000
ESPP [Member]
Weighted Average Grant Date Fair Value [Abstract]
Discount from market price at date of purchase	5.00%		5.00%
Total stock purchases under the plan (in shares)	1,081
Shares reserved for issuance (in shares)	244,372
ESPP [Member] | Minimum [Member]
Weighted Average Grant Date Fair Value [Abstract]
Discount from market price at date of purchase	0.00%
ESPP [Member] | Maximum [Member]
Weighted Average Grant Date Fair Value [Abstract]
Discount from market price at date of purchase	15.00%