Securities (Schedule of Securities by Contractual Maturity) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Securities Available-for-Sale: Amortized cost
Due in one year or less	$ 3,768
Due after one year through five years	17,960
Due after five years through ten years	72,853
Due after ten years	72,740
Total Amortized Cost	626,383	614,085
Securities Available-for-Sale: Fair Value
Due in one year or less	3,815
Due after one year through five years	17,895
Due after five years through ten years	75,597
Due after ten years	76,031
Total Fair Value	630,995	606,032
Securities Held-to-Maturity: Carrying Amount
Due in one year or less	0
Due after one year through five years	184
Due after five years through ten years	0
Due after ten years	0
Total Carrying Amount	184	268
Securities Held-to-Maturity: Fair Value
Due in one year or less	0
Due after one year through five years	186
Due after five years through ten years	0
Due after ten years	0
Total Fair Value	186	271
Mortgage-backed Securities – Residential
Securities Available-for-Sale: Amortized cost
Available-for-Sale, amortized cost	458,709
Total Amortized Cost	458,709	481,724
Securities Available-for-Sale: Fair Value
Available-for-Sale, Fair Value	457,304
Total Fair Value	457,304	473,230
Equity Securities
Securities Available-for-Sale: Amortized cost
Available-for-Sale, amortized cost	353
Total Amortized Cost	353	353
Securities Available-for-Sale: Fair Value
Available-for-Sale, Fair Value	353
Total Fair Value	$ 353	$ 353