FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Marketable debt securities	$ 0	$ 49,995,000
Proceeds from maturities of marketable debt securities	50,000,000	50,000,000	$ 25,000,000
Gross realized gains (losses) from the maturities of available-for-sale marketable debt securities	0	0
Impairment on ROU assets, leasehold improvements, and furniture and equipment	12,671,000	$ 169,000	$ 30,000
Impairment charges due to reducing real estate footprint	$ 9,600,000

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Amount of realized gain (loss) on 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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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Amount of loss from impairment of right-of-use asset from operating lease.

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Amount of cash inflow from sale, maturity, prepayment and call 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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