Securities (Schedule of Information Regarding Securities with Unrealized Losses) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Securities in an Unrealized Loss Position for Less than 12 Months
Total temporarily impaired securities Fair Value	$ 164,154	$ 75,474
Total temporarily impaired securities Unrealized Losses	925	329
Securities in an Unrealized Loss Position for More than 12 Months
Total temporarily impaired securities Fair Value	35,531	37,392
Total temporarily impaired securities Unrealized Losses	1,013	1,299
Total temporarily impaired securities Fair Value	199,685	112,866
Total temporarily impaired securities Unrealized Losses	$ 1,938	1,628
Government-sponsored enterprises securities [Member]
Securities in an Unrealized Loss Position for Less than 12 Months
AFS Fair Value		5,489
AFS Unrealized Losses		11
Securities in an Unrealized Loss Position for More than 12 Months
AFS Fair Value	$ 2,991	2,953
AFS Unrealized Losses	8	47
Total temporarily impaired securities Fair Value	2,991	8,442
Total temporarily impaired securities Unrealized Losses	8	58
Mortgage-backed securities [Member]
Securities in an Unrealized Loss Position for Less than 12 Months
AFS Fair Value	141,334	69,985
AFS Unrealized Losses	685	318
Securities in an Unrealized Loss Position for More than 12 Months
AFS Fair Value	31,578	33,557
AFS Unrealized Losses	934	1,104
Total temporarily impaired securities Fair Value	172,912	103,542
Total temporarily impaired securities Unrealized Losses	1,619	$ 1,422
Corporate bonds [Member]
Securities in an Unrealized Loss Position for Less than 12 Months
AFS Fair Value	21,991
AFS Unrealized Losses	219
Securities in an Unrealized Loss Position for More than 12 Months
AFS Fair Value	940	$ 865
AFS Unrealized Losses	60	135
Total temporarily impaired securities Fair Value	22,931	865
Total temporarily impaired securities Unrealized Losses	$ 279	$ 135
Equity securities [Member]
Securities in an Unrealized Loss Position for Less than 12 Months
AFS Fair Value
AFS Unrealized Losses
Securities in an Unrealized Loss Position for More than 12 Months
AFS Fair Value	$ 22	$ 17
AFS Unrealized Losses	11	13
Total temporarily impaired securities Fair Value	22	17
Total temporarily impaired securities Unrealized Losses	11	$ 13
States and local governments [Member]
Securities in an Unrealized Loss Position for Less than 12 Months
HTM Fair Value	829
HTM Unrealized Losses	$ 21
Securities in an Unrealized Loss Position for More than 12 Months
HTM Fair Value
HTM Unrealized Losses
Total temporarily impaired securities Fair Value	$ 829
Total temporarily impaired securities Unrealized Losses	$ 21