Securities (Amortized Cost and Estimated Fair Values of Debt Securities by Contractual Maturity) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Available-for-sale, Amortized Cost
Due in one year or less	$ 1,654
Due after one year through five years	29,753
Due after five years through ten years	155,014
Due after ten years	634,307
Total	820,728
Available-for-sale, Fair Value
Due in one year or less	1,667
Due after one year through five years	30,433
Due after five years through ten years	155,315
Due after ten years	621,062
Total	$ 808,477