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COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Contract amount of commitments and contingencies | $ 1,103,786 | $ 796,098
Unused lines of credit | 25,000 |
Federal Home Loan Bank unused borrowing capacity | 1,680,000 |
Federal Reserve unused borrowing capacity | 22,900 |
Federal Reserve required average total reserve | 84,800 |
Federal Reserve requirement represented by cash on hand | 73,200 |
Required deposit with Federal Reserve | 11,600 |
Minimum [Member] |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Range of reasonably possible losses for such matters in the aggregate, beyond the existing recorded liability | 0 |
Maximum [Member] |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Range of reasonably possible losses for such matters in the aggregate, beyond the existing recorded liability | 1,000 |
Commitments to Extend Credit [Member] |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Contract amount of commitments and contingencies | 1,080,004 | 773,442
Standby Letters of Credit [Member] |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Contract amount of commitments and contingencies | $ 23,782 | $ 22,656

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- Definition Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22 (b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 + Details
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