Investments (Investments Classified by Contractual Maturity Date) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Amortized Cost And Estimated Fair Value Of Investment Securities Available For Sale By Contractual Maturity [Line Items]
Maturing within one year, Amortized Cost	$ 4,119	$ 686
Maturing after one year through five years, Amortized Cost	244,792	222,081
Maturing after five years through ten years, Amortized Cost	58,634	97,949
Maturing after ten years, Amortized Cost	50,736	54,531
Amortized Cost, Total	503,936	504,564
Maturing within one year, Fair Value	4,160	694
Maturing after one year through five years, Fair Value	247,764	225,415
Maturing after five years through ten years, Fair Value	59,743	99,583
Maturing after ten years, Fair Value	51,444	55,705
Fair Value, Total	509,600	511,883
U.S Government agencies collateralized by mortgage obligations [Member]
Amortized Cost And Estimated Fair Value Of Investment Securities Available For Sale By Contractual Maturity [Line Items]
Investment securities not due at a single maturity date, Amortized Cost	144,996	128,107
Investment securities not due at a single maturity date, Fair Value	145,193	128,264
Other securities [Member]
Amortized Cost And Estimated Fair Value Of Investment Securities Available For Sale By Contractual Maturity [Line Items]
Amortized Cost, Total	659	1,210
Fair Value, Total	$ 1,296	$ 2,222