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LEASES (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Operating Leases [Abstract] |  |  |
Term of option to terminate | 1 year |  |
Components of Lease Expense [Abstract] |  |  |
Operating lease cost | $ 9,000 | $ 8,724 |
Variable lease cost | 53 | 18 |
Short-term lease cost | 369 | 240 |
Total lease cost | 9,422 | 8,982 |
Rental expense |  |  | $ 9,000
Cash paid for amounts included in the measurement of lease liabilities [Abstract] |  |  |
Operating cash outflows for operating leases | 8,478 | 7,938 |
Right-of-use assets obtained in exchange for lease obligations [Abstract] |  |  |
Operating leases | 3,519 | 14,145 |
Operating leases [Abstract] |  |  |
Operating lease right-of-use assets | $ 34,908 | 39,895 |
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List] | us-gaap:PropertyPlantAndEquipmentNet |  |
Operating lease liabilities | $ 35,857 | $ 40,913 |
Operating Lease, Liability, Statement of Financial Position [Extensible List] | us-gaap:OperatingLeaseLiability | us-gaap:OperatingLeaseLiability |
Weighted average remaining lease term [Abstract] |  |  |
Operating leases | 6 years 1 month 6 days | 6 years 7 months 6 days |
Weighted average discount rate [Abstract] |  |  |
Operating leases | 2.82% | 2.95% |
Minimum [Member] |  |  |
Operating Leases [Abstract] |  |  |
Remaining term of lease | 1 year |  |
Term of option to extend | 1 year |  |
Maximum [Member] |  |  |
Operating Leases [Abstract] |  |  |
Remaining term of lease | 14 years |  |
Term of option to extend | 40 years |  |

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