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FAIR VALUE, Carrying Amounts and Estimated Fair Values of Other Financial Instruments (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Carrying Value [Member] |  |
Financial assets [Abstract] |  |
Net loans | $ 6,209,174 | $ 4,901,329
Financial liabilities [Abstract] |  |
Deposits | 8,444,420 | 7,075,954
Short-term borrowings | 24,000 | 146,200
Securities sold under agreement to repurchase, short-term | 337,011 | 0
Other long-term debt | 2,071 | 0
Subordinated debt held by unconsolidated subsidiary trusts | 122,814 | 102,170
Fair Value [Member] |  |
Financial assets [Abstract] |  |
Net loans | 6,244,941 | 4,935,140
Financial liabilities [Abstract] |  |
Deposits | 8,431,481 | 7,071,191
Short-term borrowings | 24,000 | 146,200
Securities sold under agreement to repurchase, short-term | 337,011 | 0
Other long-term debt | 2,021 | 0
Subordinated debt held by unconsolidated subsidiary trusts | $ 122,814 | $ 90,144

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- Definition Fair value portion of debt having initial terms less than one year or the normal operating cycle, if longer. + References No definition available. + Details
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- Definition Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits. + References No definition available. + Details
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- Definition Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -URI http://asc.fasb.org/subtopic&trid=2196772 + Details
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- Definition Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611 + Details
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