Fair Value of Financial Instruments (Fair Values of Financial Assets and Liabilities on Balance Sheets) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Financial assets:
Cash and cash equivalents	$ 63,741	$ 61,454
Investment securities	878,916	713,633
Loans	1,990,941	1,581,813
Financial liabilities:
Deposits	2,535,874	1,938,021
Short-term borrowings	129,165	88,277
Long-term borrowings	121,753	183,878
Carrying Amount
Financial assets:
Cash and cash equivalents	63,741	61,454
Investment securities	878,180	713,659
Loans	2,028,550	1,607,391
Financial liabilities:
Deposits	2,530,856	1,933,074
Short-term borrowings	129,165	88,277
Long-term borrowings	$ 116,400	$ 179,083