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Investment Securities (Details 3) (USD $) In Thousands, unless otherwise specified | Jun. 30, 2014 | Dec. 31, 2013
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Available for sale: |  |
Fair value, less than 12 Months | $ 223,881 | $ 2,534,354
Unrealized losses, less than 12 Months | (971) | (101,585)
Fair value, 12 Months or More | 2,291,359 | 434,554
Unrealized losses, 12 Months or More | (59,478) | (31,534)
Fair value, total | 2,515,240 | 2,968,908
Unrealized losses, total | (60,449) | (133,119)
Mortgage Backed Securities [Member] |  |
Available for sale: |  |
Fair value, less than 12 Months | 219,141 | 2,459,565
Unrealized losses, less than 12 Months | (755) | (98,022)
Fair value, 12 Months or More | 2,240,363 | 420,262
Unrealized losses, 12 Months or More | (53,636) | (26,552)
Fair value, total | 2,459,504 | 2,879,827
Unrealized losses, total | (54,391) | (124,574)
U S States And Political Subdivisions [Member] |  |
Available for sale: |  |
Fair value, less than 12 Months | 4,740 | 55,327
Unrealized losses, less than 12 Months | (216) | (3,025)
Fair value, 12 Months or More | 40,487 | 14,292
Unrealized losses, 12 Months or More | (5,601) | (4,982)
Fair value, total | 45,227 | 69,619
Unrealized losses, total | (5,817) | (8,007)
Equity Securities [Member] |  |
Available for sale: |  |
Fair value, less than 12 Months |  | 19,462
Unrealized losses, less than 12 Months |  | (538)
Fair value, 12 Months or More | 10,509 |
Unrealized losses, 12 Months or More | (241) |
Fair value, total | 10,509 | 19,462
Unrealized losses, total | $ (241) | $ (538)

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- Definition Amount of accumulated unrealized loss on securities classified as available-for-sale securities that have been in a loss position for less than twelve months impacting investments. + References No definition available. + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities. + References 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)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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