Loans, Non-accrual and Past Due Loans (Details) $ in Thousands	Dec. 31, 2015 USD ($) Loan	Dec. 31, 2014 USD ($) Loan	Dec. 31, 2013 USD ($)
Non-accrual and Past Due Loans [Abstract]
Non-accrual loans	$ 2,728	$ 5,237
Total past due	1,090	2,425
Current	613,005	542,810
Total	614,095	545,235	$ 515,002
Loans 90 days past due and still accruing	2	0
30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	367	1,174
60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	5	1
90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	718	1,250
Commercial [Member]
Non-accrual and Past Due Loans [Abstract]
Non-accrual loans	$ 112	$ 2,151
Number of nonaccrual loans | Loan	4	7
Total past due	$ 275	$ 82
Current	135,820	120,669
Total	136,095	120,751	110,644
Commercial [Member] | 30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	218	0
Commercial [Member] | 60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	0	0
Commercial [Member] | 90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	57	82
Commercial Real Estate [Member]
Non-accrual and Past Due Loans [Abstract]
Non-accrual loans	$ 964	$ 672
Number of nonaccrual loans | Loan	4	5
Total past due	$ 362	$ 239
Current	291,954	256,716
Total	292,316	256,955	235,296
Commercial Real Estate [Member] | 30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	130	0
Commercial Real Estate [Member] | 60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	0	0
Commercial Real Estate [Member] | 90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	232	239
Agriculture [Member]
Non-accrual and Past Due Loans [Abstract]
Non-accrual loans	0	0
Total past due	0	0
Current	84,813	61,144
Total	84,813	61,144	51,730
Agriculture [Member] | 30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	0	0
Agriculture [Member] | 60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	0	0
Agriculture [Member] | 90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	0	0
Residential Mortgage [Member]
Non-accrual and Past Due Loans [Abstract]
Non-accrual loans	$ 1,092	$ 1,691
Number of nonaccrual loans | Loan	4	6
Total past due	$ 0	$ 1,629
Current	43,375	48,882
Total	43,375	50,511	52,809
Residential Mortgage [Member] | 30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	0	1,172
Residential Mortgage [Member] | 60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	0	0
Residential Mortgage [Member] | 90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	0	457
Residential Construction [Member]
Non-accrual and Past Due Loans [Abstract]
Non-accrual loans	0	$ 71
Number of nonaccrual loans | Loan		2
Total past due	0	$ 0
Current	12,110	5,963
Total	12,110	5,963	10,444
Residential Construction [Member] | 30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	0	0
Residential Construction [Member] | 60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	0	0
Residential Construction [Member] | 90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	0	0
Consumer [Member]
Non-accrual and Past Due Loans [Abstract]
Non-accrual loans	$ 560	$ 652
Number of nonaccrual loans | Loan	4	5
Total past due	$ 453	$ 475
Current	44,933	49,436
Total	45,386	49,911	$ 54,079
Consumer [Member] | 30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	19	2
Consumer [Member] | 60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	5	1
Consumer [Member] | 90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Total past due	$ 429	$ 472