Investment Securities (Schedule Of Fair Value And Unrealized Losses Of Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Investment Holdings [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	$ 475,989	$ 231,677
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	3,397	1,362
Available-for-sale Securities, 12 Months or Longer, Fair Value	320,874	503,646
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	5,626	10,539
Available-for-sale Securities, Fair Value	796,863	735,323
Available-for-sale Securities, Unrealized Losses	9,023	11,901
Held-to-maturity Securities, Less than 12 Months, Fair Value	39	224
Held-to-maturity Securities, Less than 12 Months, Unrealized Losses	1	15
Held-to-maturity Securities, 12 Months or Longer, Fair Value	0	0
Held-to-maturity Securities, 12 Months or Longer, Unrealized Losses	0	0
Held-to-maturity Securities, Fair Value	39	224
Held-to-maturity Securities, Unrealized Losses	1	15
Obligations Of States And Political Subdivisions [Member]
Investment Holdings [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	12,536	11,100
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	158	547
Available-for-sale Securities, 12 Months or Longer, Fair Value	8,034	8,550
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	657	294
Available-for-sale Securities, Fair Value	20,570	19,650
Available-for-sale Securities, Unrealized Losses	815	841
Residential Mortgage-Backed Securities And Collateralized Mortgage Obligations [Member]
Investment Holdings [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	463,453	220,577
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	3,239	815
Available-for-sale Securities, 12 Months or Longer, Fair Value	312,840	495,096
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	4,969	10,245
Available-for-sale Securities, Fair Value	776,293	715,673
Available-for-sale Securities, Unrealized Losses	8,208	11,060
Held-to-maturity Securities, Less than 12 Months, Fair Value	39	224
Held-to-maturity Securities, Less than 12 Months, Unrealized Losses	1	15
Held-to-maturity Securities, 12 Months or Longer, Fair Value	0	0
Held-to-maturity Securities, 12 Months or Longer, Unrealized Losses	0	0
Held-to-maturity Securities, Fair Value	39	224
Held-to-maturity Securities, Unrealized Losses	$ 1	$ 15

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 6

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