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FAIR VALUE, Carrying Amounts and Estimated Fair Values of Other Financial Instruments (Details) - USD ($) $ in Thousands | Sep. 30, 2017 | Dec. 31, 2016
--- | --- | ---
Carrying Value [Member] |  |
Financial assets [Abstract] |  |
Net loans | $ 6,260,737 | $ 4,901,329
Financial liabilities [Abstract] |  |
Deposits | 8,605,990 | 7,075,954
Short-term borrowings | 0 | 146,200
Securities sold under agreement to repurchase, short-term | 310,703 | 0
Other long-term debt | 3,586 | 0
Subordinated debt held by unconsolidated subsidiary trusts | 122,808 | 102,170
Fair Value [Member] |  |
Financial assets [Abstract] |  |
Net loans | 6,321,781 | 4,935,140
Financial liabilities [Abstract] |  |
Deposits | 8,592,459 | 7,071,191
Short-term borrowings | 0 | 146,200
Securities sold under agreement to repurchase, short-term | 310,703 | 0
Other long-term debt | 3,568 | 0
Subordinated debt held by unconsolidated subsidiary trusts | $ 122,808 | $ 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 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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