Loans - Impaired Loans - Average Recorded Investment and Interest Income Recognized (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Average Recorded Investment
With no related allowance recorded	$ 20,798	$ 21,425
With an allowance recorded	645	1,377
Total impaired loans	21,443	22,802
Interest Income Recognized
With no related allowance recorded	101	153
Total impaired loans	101	153
Commercial
Average Recorded Investment
With no related allowance recorded	128	299
With an allowance recorded		1
Lease financing receivables
Average Recorded Investment
With no related allowance recorded	293
With an allowance recorded	120
Real estate - commercial | Owner occupied general purpose
Average Recorded Investment
With no related allowance recorded	1,170	2,494
Interest Income Recognized
With no related allowance recorded		44
Real estate - commercial | Owner occupied special purpose
Average Recorded Investment
With no related allowance recorded	376	650
Real estate - commercial | Non-owner occupied general purpose
Average Recorded Investment
With no related allowance recorded	1,443	1,573
With an allowance recorded	123	306
Interest Income Recognized
With no related allowance recorded	1	1
Real estate - commercial | Non-owner occupied special purpose
Average Recorded Investment
With no related allowance recorded	507
With an allowance recorded		825
Real estate - commercial | Retail properties
Average Recorded Investment
With no related allowance recorded	1,161	1,017
Real estate - commercial | Farm
Average Recorded Investment
With no related allowance recorded		636
Real estate - residential | Investor
Average Recorded Investment
With no related allowance recorded	1,708	1,879
Interest Income Recognized
With no related allowance recorded	20	23
Real estate - residential | Multifamily
Average Recorded Investment
With no related allowance recorded	2,412
Real estate - residential | Owner occupied
Average Recorded Investment
With no related allowance recorded	9,016	10,124
With an allowance recorded	402	222
Interest Income Recognized
With no related allowance recorded	65	79
Real estate - residential | Revolving and junior liens
Average Recorded Investment
With no related allowance recorded	2,227	2,673
With an allowance recorded		23
Interest Income Recognized
With no related allowance recorded	15	6
Consumer
Average Recorded Investment
With no related allowance recorded	105
Construction Loans | Real estate - commercial | Commercial speculative
Average Recorded Investment
With no related allowance recorded	72	$ 80
Construction Loans | Real estate - commercial | All other
Average Recorded Investment
With no related allowance recorded	$ 180