Securities (Schedule of Information Regarding Securities with Unrealized Losses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Securities in an Unrealized Loss Position for Less than 12 Months
Total temporarily impaired securities Fair Value	$ 86,232	$ 75,474
Total temporarily impaired securities Unrealized Losses	404	329
Securities in an Unrealized Loss Position for More than 12 Months
Total temporarily impaired securities Fair Value	33,187	37,392
Total temporarily impaired securities Unrealized Losses	1,074	1,299
Total temporarily impaired securities Fair Value	119,419	112,866
Total temporarily impaired securities Unrealized Losses	1,478	1,628
US 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	2,977	2,953
AFS Unrealized Losses	23	47
Total temporarily impaired securities Fair Value	2,977	8,442
Total temporarily impaired securities Unrealized Losses	23	58
Mortgage-backed securities [Member]
Securities in an Unrealized Loss Position for Less than 12 Months
AFS Fair Value	86,232	69,985
AFS Unrealized Losses	404	318
Securities in an Unrealized Loss Position for More than 12 Months
AFS Fair Value	29,291	33,557
AFS Unrealized Losses	938	1,104
Total temporarily impaired securities Fair Value	115,523	103,542
Total temporarily impaired securities Unrealized Losses	1,342	1,422
Corporate bonds [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	900	865
AFS Unrealized Losses	100	135
Total temporarily impaired securities Fair Value	900	865
Total temporarily impaired securities Unrealized Losses	100	135
Equities [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	19	17
AFS Unrealized Losses	13	13
Total temporarily impaired securities Fair Value	19	17
Total temporarily impaired securities Unrealized Losses	13	13
States and local governments [Member]
Securities in an Unrealized Loss Position for Less than 12 Months
HTM Fair Value
HTM Unrealized Losses
Securities in an Unrealized Loss Position for More than 12 Months
HTM Fair Value
HTM Unrealized Losses
Total temporarily impaired securities Fair Value
Total temporarily impaired securities Unrealized Losses

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