Investment Securities Gross Unrealized Losses - HTM (Details) - State and political subdivisions [Member] $ in Thousands	Sep. 30, 2016 USD ($) securities	Dec. 31, 2015 USD ($)
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, securities in unrealized loss positions, qualitative disclosure, number of positions | securities	11
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, fair value	$ 621	$ 2,832
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, gross unrealized (losses)	(7)	(42)
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, fair value	4,009	7,341
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, gross unrealized (losses)	(174)	(182)
Held-to-maturity securities, continuous unrealized loss position, fair value	4,630	10,173
Held-to-maturity securities, continuous unrealized loss position, gross unrealized (losses)	$ (181)	$ (224)