Summary of Significant Accounting Policies, Letters of Credit Facility, Statement of Cash Flows and Earnings Per Share (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017 USD ($) shares	Mar. 31, 2016 USD ($)	Dec. 31, 2016 shares
Statement of Cash Flows [Abstract]
Federal and state tax paid	$ 14	$ 105
Property and equipment additions	$ 836	350
Earnings Per Share [Abstract]
Weighted average number of shares outstanding (in shares) | shares	4,217,596		4,217,596
Potentially dilutive securities (in shares) | shares	0		0
Wells Fargo Bank [Member] | Standby Letter of Credit [Member]
Letter of Credit Facility [Abstract]
Line of credit facility, maximum borrowing capacity	$ 60,000
Stand-by letters of credit	$ 0	$ 1,000
Current ratio	1.1