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INVESTMENT SECURITIES, Cash Flow Information on Investment Securities (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Cash flow information on investment securities [Abstract] |  |  |
Gross gains on sales of investment securities | $ 3 | $ 0 | $ 96,258
Gross losses on sales of investment securities | 7 | 0 | 15,490
Proceeds from the maturities of mortgage-backed securities and CMO's | 45,432 | 46,791 | 83,232
Purchases of mortgage backed securities and CMO's | 18,477 | 22,234 | $ 51,194
Investment securities pledged to collateralize certain deposits and borrowings | $ 1,750,000 | $ 1,182,000 |

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- Definition The cash inflow associated with the aggregate amount received by the entity through sale or maturity of mortgage-backed securities and CMO's during the period. + References No definition available. + Details
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- Definition The cash outflow associated with the aggregate amount received by the entity through sale or maturity of mortgage-backed securities and CMO's during the period. + References No definition available. + Details
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- Definition This item represents the gross profit realized on the sale of debt or equity securities 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 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563 + Details
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- Definition This item represents the gross loss realized on the sale of debt or equity securities 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 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563 + 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=49124121&loc=d3e5086-111524 + Details
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