Commitments and Contingencies (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Commitments to extend credit: | Home equity
Other Commitments [Line Items]
Contractual obligations	$ 196,946	$ 194,477
Commitments to extend credit: | Commercial real estate
Other Commitments [Line Items]
Contractual obligations	45,832	66,901
Commitments to extend credit: | Other commitments
Other Commitments [Line Items]
Contractual obligations	159,622	184,895
Standby letters of credit
Other Commitments [Line Items]
Contractual obligations	7,098	7,151
Commercial letters of credit
Other Commitments [Line Items]
Contractual obligations	$ 863	$ 831