Income Taxes - Income tax provision from operations included in consolidated statements of operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Current:
Federal	$ 675	$ 691
State	1	(1)
Total current tax	676	690
Deferred:
Federal	82	27
State	0	0
Total deferred	82	27
Income tax provision, total	$ 758	$ 717