Securities Narrative (Details)	12 Months Ended
	Dec. 31, 2015 USD ($) Security	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Investments, Debt and Equity Securities [Abstract]
Proceeds from sales of securities	$ 11,600,000	$ 58,900,000	$ 24,200,000
Called securities | Security	2
Gross gains realized on sale of securities	$ 177,000	770,000	732,000
Gross loss realized on sale of securities	37,000	584,000	314,000
Net impairment losses	0	0	0
Tax expense related to realized gains	48,000	63,000	$ 142,000
Carrying value of securities pledged for fiduciary powers	$ 113,100,000	$ 125,700,000
Number of securities temporarily impaired | Security	212
Number of securities temporarily impaired in investment grade | Security	209
Number of securities temporarily impaired in speculative grade | Security	3