Fair Value of Financial Instruments (Fair Values of Financial Assets and Liabilities on Balance Sheets) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financial assets:
Cash and cash equivalents	$ 63,296	$ 71,115
Investment securities	886,798	868,955
Loans (1)	2,057,998	2,018,482
Financial liabilities:
Deposits	2,591,488	2,540,131
Short-term borrowings	135,068	160,386
Long-term borrowings	118,190	117,299
Carrying Amount
Financial assets:
Cash and cash equivalents	63,296	71,115
Investment securities	885,462	868,830
Loans (1)	2,088,804	2,057,614
Financial liabilities:
Deposits	2,587,083	2,535,944
Short-term borrowings	135,068	160,386
Long-term borrowings	$ 113,188	$ 113,670