FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair value measurements
Cash and cash equivalents	$ 105,840	$ 166,841
Available for sale securities	241,407	188,282
Trading securities	89,736	73,828
Fair value measured on a recurring basis
Fair value measurements
Cash and cash equivalents	105,840	166,841
Available for sale securities	241,407	188,282
Trading securities	89,736	73,828
Total assets measured at fair value	437,533	430,670
Fair value measured on a recurring basis \| Foreign currency forward contracts
Fair value measurements
Derivative instruments, net	426	778
Fair value measured on a recurring basis \| Commodity futures contracts
Fair value measurements
Derivative instruments, net	124	941
Fair value measured on a recurring basis \| Level 1
Fair value measurements
Cash and cash equivalents	105,840	166,841
Available for sale securities	1,282	3,149
Trading securities	76,196	61,431
Total assets measured at fair value	183,442	232,362
Fair value measured on a recurring basis \| Level 1 \| Commodity futures contracts
Fair value measurements
Derivative instruments, net	124	941
Fair value measured on a recurring basis \| Level 2
Fair value measurements
Available for sale securities	240,125	185,133
Trading securities	13,540	12,397
Total assets measured at fair value	254,091	198,308
Fair value measured on a recurring basis \| Level 2 \| Foreign currency forward contracts
Fair value measurements
Derivative instruments, net	$ 426	$ 778

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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