Loans - Carrying Amount of Purchased Credit Impaired Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Accounts Notes And Loans Receivable [Line Items]
Total impaired loans	$ 4,570	$ 8,950
Unaccreted discount on purchased credit impaired loans	(1,198)	(2,291)
Receivables Acquired with Deteriorated Credit Quality
Accounts Notes And Loans Receivable [Line Items]
Total	3,373	6,659
Commercial Real Estate | Receivables Acquired with Deteriorated Credit Quality
Accounts Notes And Loans Receivable [Line Items]
Total	177	354
Commercial and Industrial Loans
Accounts Notes And Loans Receivable [Line Items]
Total impaired loans	4,258	6,787
Commercial and Industrial Loans | Receivables Acquired with Deteriorated Credit Quality
Accounts Notes And Loans Receivable [Line Items]
Total	3,196	5,165
Consumer Loans
Accounts Notes And Loans Receivable [Line Items]
Total impaired loans	17	14
Land | Receivables Acquired with Deteriorated Credit Quality
Accounts Notes And Loans Receivable [Line Items]
Total		1,140
Real Estate Loans
Accounts Notes And Loans Receivable [Line Items]
Total impaired loans	295	2,149
Real Estate Loans | Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total impaired loans	$ 295	533
Real Estate Loans | Land
Accounts Notes And Loans Receivable [Line Items]
Total impaired loans		$ 1,616