Guarantees (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Commitments to Extend Credit
Loan Commitments and Letters of Credit [Line Items]
Notional Amount	$ 294,618	$ 383,586	$ 284,284
Fair Value	0	0	0
Standby Letters of Credit
Loan Commitments and Letters of Credit [Line Items]
Notional Amount	3,371	3,445	2,927
Fair Value	$ 28	$ 30	$ 22
Minimum | Standby Letters of Credit
Loan Commitments and Letters of Credit [Line Items]
Loans And Leases Receivable, Loan Commitments, Fixed Fees, Percent	1.00%
Maximum | Standby Letters of Credit
Loan Commitments and Letters of Credit [Line Items]
Loans And Leases Receivable, Loan Commitments, Fixed Fees, Percent	3.00%