LONG-TERM DEBT AND FINANCING ARRANGEMENTS - Summary of Long-term Debt Payable (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total debt	$ 260,086	$ 270,438
Less current portion due within one year	(8,609)	(9,789)
Total long-term debt, excluding current portion	$ 251,477	260,649
Term loan, net of debt issuance costs
Debt Instrument [Line Items]
Debt instrument, effective interest rate (as a percent)	2.10%
Total debt	$ 172,876	135,938
Revolving Credit Facility \| Revolver loan
Debt Instrument [Line Items]
Debt instrument, effective interest rate (as a percent)	2.10%
Total debt	$ 87,210	$ 134,500

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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