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COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Loss Contingency, Estimate [Abstract] |  |
Contract amount of commitments and contingencies | $ 1,181,652 | $ 1,167,745
Unused lines of credit | 25,000 |
Federal Home Loan Bank unused borrowing capacity | 1,800,000 |
Federal Reserve unused borrowing capacity | 25,100 |
Federal Reserve required average total reserve | 100,300 |
Federal Reserve requirement represented by cash on hand | 77,200 |
Required deposit with Federal Reserve | 23,100 |
Minimum [Member] |  |
Loss Contingency, Estimate [Abstract] |  |
Range of reasonably possible losses for such matters in the aggregate, beyond the existing recorded liability | 0 |
Maximum [Member] |  |
Loss Contingency, Estimate [Abstract] |  |
Range of reasonably possible losses for such matters in the aggregate, beyond the existing recorded liability | 1,000 |
Commitments to Extend Credit [Member] |  |
Loss Contingency, Estimate [Abstract] |  |
Contract amount of commitments and contingencies | 1,143,780 | 1,134,576
Standby Letters of Credit [Member] |  |
Loss Contingency, Estimate [Abstract] |  |
Contract amount of commitments and contingencies | $ 37,872 | $ 33,169

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- Definition Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 3: http://fasb.org/us-gaap/role/ref/legacyRef -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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