Allowance for Credit Losses, Loans by Class Modified as Troubled Debt Restructured Loans (Details) (USD $)	12 Months Ended
	Dec. 31, 2014 Loan	Dec. 31, 2013 Loan
Financing Receivable, Modifications [Line Items]
Specific reserves	$ 1,300,000	$ 1,200,000
Troubled debt restructured loans	6,600,000	6,800,000
Commitments to lend additional amounts to customers with outstanding loans that are classified as troubled debt restructurings	0	0
Period of modifications involving a reduction of stated interest rate of the loan		5 years
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans	11	12
Pre-Modification Outstanding Recorded Investment	1,012,000	5,736,000
Post-Modification Recorded Outstanding Investment	950,000	5,693,000
Increase in allowance for loan losses due to TDR	28,000	0
TDR's charge-offs	63,000	43,000
Period after which loan is considered to be in payment default	90 days
Charge offs on troubled debt restructurings that subsequently defaulted		0
Minimum [Member]
Financing Receivable, Modifications [Line Items]
Period of modifications involving a reduction of stated interest rate of the loan	4 years
Period of modifications involving extension of maturity date	6 months	6 months
Maximum [Member]
Financing Receivable, Modifications [Line Items]
Period of modifications involving a reduction of stated interest rate of the loan	30 years
Period of modifications involving extension of maturity date	30 years	10 years
Performing [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructured loans, performing	5,000,000	4,600,000
Residential 1st Mortgages [Member]
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans	5	4
Pre-Modification Outstanding Recorded Investment	857,000	306,000
Post-Modification Recorded Outstanding Investment	804,000	290,000
Home Equity Lines and Loans [Member]
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans	3	4
Pre-Modification Outstanding Recorded Investment	98,000	414,000
Post-Modification Recorded Outstanding Investment	89,000	387,000
Agricultural [Member]
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans	1
Pre-Modification Outstanding Recorded Investment	32,000
Post-Modification Recorded Outstanding Investment	32,000
Commercial [Member]
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans	1	4
Pre-Modification Outstanding Recorded Investment	18,000	5,016,000
Post-Modification Recorded Outstanding Investment	18,000	5,016,000
Number of loans modified as troubled debt restructurings with subsequent payment defaults		1
Loans modified as troubled debt restructurings with subsequent payment defaults		174,000
Consumer & Other [Member]
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans	1
Pre-Modification Outstanding Recorded Investment	7,000
Post-Modification Recorded Outstanding Investment	$ 7,000