Affordable Housing Tax Credit Limited Partnership (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Affordable housing tax credit investment	$ 3,000		$ 2,000
Less amortization	220		93
Net affordable housing tax credit investment	2,780		1,907
Unfunded commitment	$ 2,372		$ 1,617
Funding period for unfunded commitment (in years)	10 years
Tax credits and other tax benefits recognized	$ 119	$ 83
Tax credit amortization expense included in provision for income taxes	$ 126	$ 62