Securities (Schedule of by Contractual Maturity) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Securities Available-for-Sale: Amortized cost
Due in one year or less	$ 7,109
Due after one year through five years	19,186
Due after five years through ten years	66,484
Due after ten years	105,040
Total Amortized Cost	617,925	$ 626,383
Securities Available-for-Sale, Fair Value
Due in one year or less	7,213
Due after one year through five years	19,449
Due after five years through ten years	69,404
Due after ten years	107,246
Total Fair Value	625,144	630,995
Securities Held-to-Maturity, Carrying Amount
Due in one year or less	95
Due after one year through five years	0
Due after five years through ten years	0
Due after ten years	0
Total Carrying Amount	95	184
Securities Held-to-Maturity, Fair Value
Due in one year or less	95
Due after one year through five years	0
Due after five years through ten years	0
Due after ten years	0
Total Fair Value	95	186
Mortgage-backed Securities - Residential
Securities Available-for-Sale: Amortized cost
Amortized cost	419,753
Total Amortized Cost	419,753	458,709
Securities Available-for-Sale, Fair Value
Fair value	421,479
Total Fair Value	421,479	457,304
Equity Securities
Securities Available-for-Sale: Amortized cost
Amortized cost	353
Total Amortized Cost	353	353
Securities Available-for-Sale, Fair Value
Fair value	353
Total Fair Value	$ 353	$ 353