Investment in Limited Partnership (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Equity Method Investments [Line Items]
Loss on California tax credit partnership	$ 109,000	$ 158,000	$ 73,000
Investment tax credit	1,800,000
Tax credits utilized for income tax	0	0	0
Income	$ 7,000	$ 900	$ 0
Limited Partnership
Schedule of Equity Method Investments [Line Items]
Ownership (percent)	9.14%
Total investment	$ 1,601,000