DEBT - Rollforward (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Long-term debt
Long-term portion	$ 22,340	$ 24,080
Term Loan
Long-term debt
Balance, beginning of year	48,160	49,516
Interest expense	4,166	5,394
Interest payments	(3,646)	(4,875)
Balance, end of year	48,680	48,160
Less current portion	4,000
Long-term portion	$ 44,680	$ 48,160

Amount of the required periodic payments applied to interest.

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Aggregate amount of interest paid or due on all long-term debt.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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