ACCOUNTS PAYABLE, ACCRUED EXPENSES AND OTHER CURRENT LIABILITIES - Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Other current liabilities
Operating lease liabilities	$ 5,698	$ 7,609
Other	764	1,696
Total	$ 6,462	$ 9,305

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

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Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are due within one year or operating cycle, if longer, from the balance sheet date.

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