Disclosures about Fair Value of Financial Instruments (Summary of the Company's Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Cash and cash equivalents, Carrying Amount	$ 203,954	$ 230,933	$ 228,110	$ 266,743
Investment in securities, Carrying Amount	422,665	441,534
Loans, net, Carrying Amount	762,082	711,362
Accrued interest receivable, Carrying Amount	6,706	7,069
Assets, Carrying Amount	1,395,407	1,390,898
Cash and cash equivalents, Fair Value	203,954	230,933
Investment in securities, Fair Value	422,665	441,534
Loans, net, Fair Value	776,653	711,090
Accrued interest receivable, Fair Value	6,706	7,069
Assets, Fair Value	1,409,978	1,390,626
Deposits, Carrying Amount	757,136	721,926
Accounts and drafts payable, Carrying Amount	684,295	694,360
Accrued interest payable, Carrying Amount	103	91
Liabilities, Carrying Amount	1,441,534	1,416,377
Deposits, Fair Value	757,790	722,018
Accounts and drafts payable, Fair Value	684,295	694,360
Accrued interest payable, Fair Value	103	91
Liabilities, Fair Value	$ 1,442,188	$ 1,416,469