Income Taxes (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Federal:
Current	$ 455,000	$ 777,000
Deferred	421,000	514,000
Federal Income Taxes	876,000	1,291,000
State:
Current	76,000	108,000
Deferred	105,000	63,000
Total State	181,000	171,000
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Income taxes at statutory rate	1,269,000	1,461,000
State income taxes, net of federal benefit	136,000	134,000
Domestic production activities deduction	0	(77,000)
Stock compensation deferred tax asset write-off	0	25,000
Deferred true-ups	161,000	0
Effective Income Tax Rate Reconciliation, Provision to Return, Amount	152,000	0
Rate reduction	664,000	0
Other	3,000	(81,000)
Income tax expense	$ 1,057,000	$ 1,462,000
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Income taxes at statutory rate (percent)	34.00%	34.00%
State income taxes, net of federal benefit (percent)	3.60%	2.70%
Domestic production activities deduction (percent)	(0.00%)	(1.60%)
Stock compensation deferred tax asset write-off (percent)	0.00%	0.50%
Deferred true-ups (percent)	4.30%	0.00%
Effective Income Tax Rate Reconciliation, Provision to Return, Percent	4.10%	0.00%
Rate reduction (percent)	(17.80%)	0.00%
Other (percent)	0.10%	(1.60%)
Effective income tax rate (percent)	28.30%	34.00%
Components of Deferred Tax Assets and Liabilities [Abstract]
Unrealized losses on investments available for sale	$ (1,185,000)	$ (1,404,000)
Unrealized losses on investments available for sale	5,000	15,000
Retainage	(264,000)	0
Allowance for doubtful accounts	52,000	128,000
Prepaid expenses	(98,000)	0
Vacation accrued	67,000	106,000
Deferred income	0	281,000
State NOL carryforward	48,000	75,000
Other	85,000	35,000
Net deferred tax liability	$ (1,290,000)	$ (764,000)