Securities (Schedule of Contractual Maturities of Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Available for Sale, Amortized Cost
Available for sale Securities, Amortized Cost	$ 369,438	$ 365,140
Available for Sale, Fair Value
Available for sale Securities, Fair Value, Total	378,227	367,249
Held to Maturity, Amortized Cost
Held to maturity Securities, Amortized Cost	457,641	477,507
Held to Maturity, Fair Value
Held to Maturity, Fair Value, Total	467,764	$ 478,749
Debt Securities
Available for Sale, Amortized Cost
Available for Sale, Amortized Cost, Due in one year or less	500
Available for Sale, Amortized Cost, Due after one year to five years	33,068
Available for Sale, Amortized Cost, Due after five to ten years	96,153
Available for Sale, Amortized Cost, Due after ten years	225,344
Available for sale Securities, Amortized Cost	355,065
Available for Sale, Fair Value
Available for Sale, Fair Value, Due in one year or less	500
Available for Sale, Fair Value, Due after one year to five years	33,743
Available for Sale, Fair Value, Due after five to ten years	98,802
Available for Sale, Fair Value, Due after ten years	230,625
Available for sale Securities, Fair Value, Total	363,670
Held to Maturity, Amortized Cost
Held to Maturity, Amortized Cost, Due in one year or less	276
Held to Maturity, Amortized Cost, Due after one year to five years	15,263
Held to Maturity, Amortized Cost, Due after five to ten years	29,468
Held to Maturity, Amortized Cost, Due after ten years	412,634
Held to maturity Securities, Amortized Cost	457,641
Held to Maturity, Fair Value
Held to Maturity, Fair Value, Due in one year or less	277
Held to Maturity, Fair Value, Due after one year to five years	15,875
Held to Maturity, Fair Value, Due after five to ten years	30,705
Held to Maturity, Fair Value, Due after ten years	420,907
Held to Maturity, Fair Value, Total	467,764
Equity securities
Available for Sale, Amortized Cost
Available for Sale, Amortized Cost, Marketable equity securities	14,373
Available for Sale, Fair Value
Available for Sale, Fair Value, Marketable equity securities	14,557
Held to Maturity, Amortized Cost
Held to maturity Securities, Amortized Cost	0
Held to Maturity, Fair Value
Held to Maturity, Fair Value, Total	$ 0