Fair Value (Carrying Amounts and Estimated Fair Values of Company's Financial Instruments) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Financial Assets:
Loans, Net	$ 2,071,004	$ 1,975,147
FHLB Stock and Other Restricted Stock	13,048	13,048
Financial Liabilities:
Time Deposits	(381,184)	(378,181)
Level 1
Financial Assets:
Cash and Short-term Investments	44,804	48,467
Loans, Net	0	0
Accrued Interest Receivable	0	0
Financial Liabilities:
Demand, Savings, and Money Market Deposits	(2,043,388)	(1,971,370)
Time Deposits	0	0
Short-term Borrowings	0	0
Long-term Debt	0	0
Accrued Interest Payable	0	0
Level 2
Financial Assets:
Cash and Short-term Investments	9,758	16,349
Loans, Net	0	0
Accrued Interest Receivable	3,744	3,289
Financial Liabilities:
Demand, Savings, and Money Market Deposits	0	0
Time Deposits	(380,873)	(378,000)
Short-term Borrowings	(117,199)	(137,554)
Long-term Debt	(133,176)	(109,709)
Accrued Interest Payable	(873)	(775)
Level 3
Financial Assets:
Cash and Short-term Investments	0	0
Loans, Net	2,061,198	1,980,523
Accrued Interest Receivable	9,116	8,124
Financial Liabilities:
Demand, Savings, and Money Market Deposits	0	0
Time Deposits	0	0
Short-term Borrowings	0	0
Long-term Debt	(11,202)	(10,793)
Accrued Interest Payable	(59)	(14)
Carrying Value
Financial Assets:
Cash and Short-term Investments	54,562	64,816
Loans, Net	2,066,258	1,974,074
FHLB Stock and Other Restricted Stock	13,048	13,048
Accrued Interest Receivable	12,860	11,413
Financial Liabilities:
Demand, Savings, and Money Market Deposits	(2,043,388)	(1,971,370)
Time Deposits	(381,184)	(378,181)
Short-term Borrowings	(117,199)	(137,554)
Long-term Debt	(144,742)	(120,560)
Accrued Interest Payable	(932)	(789)
Total
Financial Assets:
Cash and Short-term Investments	54,562	64,816
Loans, Net	2,061,198	1,980,523
Accrued Interest Receivable	12,860	11,413
Financial Liabilities:
Demand, Savings, and Money Market Deposits	(2,043,388)	(1,971,370)
Time Deposits	(380,873)	(378,000)
Short-term Borrowings	(117,199)	(137,554)
Long-term Debt	(144,378)	(120,502)
Accrued Interest Payable	$ (932)	$ (789)