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Investment Securities, Available-for-Sale (Details Textual) (USD $) | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012
Investment Securities, Available-for-Sale |  |
Available-for-sale Securities | $ 3,222,829,000 | $ 3,683,005,000
Available-for-sale Securities, Gross Unrealized Gain Accumulated In Investments | 49,801,000 | 101,778,000
Investment securities pledged as collateral | 1,635,316,000 | 1,525,400,000
Other-than-temporary impairment on investment securities | 0 | 0
Reclassification of AFS to HTM |  |
Investment Securities, Available-for-Sale |  |
Percent Available-For-Sale Prior to Reclassification | 100.00% |
Percent Available-For-Sale Subsequent to Reclassification | 85.00% |
Percent Held-To-Maturity Subsequent to Reclassification | 15.00% |
State and local governments |  |
Investment Securities, Available-for-Sale |  |
Available-for-sale Securities | 1,385,078,000 | 1,214,518,000
Available-for-sale Securities, Gross Unrealized Gain Accumulated In Investments | 31,621,000 | 88,095,000
State and local governments | Reclassification of AFS to HTM |  |
Investment Securities, Available-for-Sale |  |
Available-for-sale Securities | 484,583,000 |
Available-for-sale Securities, Gross Unrealized Gain Accumulated In Investments | 4,624,000 |
Residential mortgage-backed securities |  |
Investment Securities, Available-for-Sale |  |
Non-guaranteed private label whole loan mortgage-backed securities | 2,602,000 | 46,733,000
Available-for-sale Securities | 1,384,622,000 | 2,160,302,000
Available-for-sale Securities, Gross Unrealized Gain Accumulated In Investments | $ 14,071,000 | $ 8,860,000

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- Definition Amount of accumulated pre-tax unrealized gains before deducting pre-tax unrealized losses on investments in available-for-sale securities impacting investments. + References No definition available. + Details
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- Details
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- Definition Investment Securities Portfolio, Percent Available-For-Sale, Prior to Reclassification + References No definition available. + Details
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- Definition Investment Securities Portfolio, Percent Available-For-Sale, Subsequent to Reclassification + References No definition available. + Details
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- Definition Investment Securities Portfolio, Percent Held-To-Maturity, Subsequent to Reclassification + References No definition available. + Details
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- Definition Non-guaranteed private label whole loan mortgage backed securities available for sale disclosure. + References No definition available. + Details
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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
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- Definition The fair value of available-for-sale securities that serve as collateral for borrowings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5086-111524 + Details
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- Definition The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e25351-111560 + Details
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