Investment Securities (Schedule Of Fair Value And Unrealized Losses Of Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Investment Holdings [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	$ 1,259,524	$ 231,677
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	14,548	1,362
Available-for-sale Securities, 12 Months or Longer, Fair Value	343,189	503,646
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	9,614	10,539
Available-for-sale Securities, Fair Value	1,602,713	735,323
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	24,162	11,901
Held-to-maturity Securities, Less than 12 Months, Fair Value		224
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		15
Held-to-maturity Securities, 12 Months or Longer, Fair Value		0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		0
Held-to-maturity Securities, Fair Value		224
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss		15
Obligations Of States And Political Subdivisions [Member]
Investment Holdings [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	2,530	11,100
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	83	547
Available-for-sale Securities, 12 Months or Longer, Fair Value	8,208	8,550
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	539	294
Available-for-sale Securities, Fair Value	10,738	19,650
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	622	841
Residential Mortgage-Backed Securities And Collateralized Mortgage Obligations [Member]
Investment Holdings [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	1,256,994	220,577
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	14,465	815
Available-for-sale Securities, 12 Months or Longer, Fair Value	334,981	495,096
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	9,075	10,245
Available-for-sale Securities, Fair Value	1,591,975	715,673
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 23,540	11,060
Held-to-maturity Securities, Less than 12 Months, Fair Value		224
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		15
Held-to-maturity Securities, 12 Months or Longer, Fair Value		0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		0
Held-to-maturity Securities, Fair Value		224
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss		$ 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
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

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