Loans and Allowance for Loan Losses - Schedule of Non-Accrual Loans, Past Due Loans over 90 Days Outstanding and Accruing and Troubled Debt Restructurings (TDR) by Class of Loans (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2017
Accounts Notes And Loans Receivable [Line Items]
Non-Accrual		$ 3,619	$ 3,165
Past Due Over 90 Days and Accruing			27
Troubled Debt Restructurings	$ 1,222	1,272
Commercial real estate
Accounts Notes And Loans Receivable [Line Items]
Non-Accrual		1,310	1,233
Troubled Debt Restructurings	$ 1,222	1,272
Commercial and industrial
Accounts Notes And Loans Receivable [Line Items]
Non-Accrual		$ 2,309	1,932
Past Due Over 90 Days and Accruing			$ 27