FAIR VALUE MEASUREMENTS (Acquisition-Related Contingent Consideration Roll Forward) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2020 USD ($)
Discount rate \| 2020 Acquisitions \| Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Measurement input to determine fair value of contingent consideration	0.175
Discount rate \| 2020 Acquisitions \| Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Measurement input to determine fair value of contingent consideration	0.155
Level 3
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Contingent consideration liabilities as of January 1, 2020	$ 10,495
Payment of contingent consideration for previously acquired business	(7,869)
Effect of net foreign currency exchange rate changes	(525)
Contingent consideration liabilities as of September 30, 2020	5,913
Level 3 \| Interest and other income, net
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Changes in the fair value of contingent consideration	(1,480)
Level 3 \| 2020 Acquisitions
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Acquisition date fair value of contingent consideration	$ 5,292

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Value of input used to measure contingent consideration liability from business combination.

+ References

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-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of increase (decrease) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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