LONG-TERM DEBT AND FINANCING ARRANGEMENTS - Summary (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term debt	$ 260,991	$ 270,438
Less portion due within one year	(9,789)	(9,789)
Total long-term debt, net of debt issuance costs	$ 251,202	260,649
Term loan, net of debt issuance costs
Debt Instrument [Line Items]
Debt instrument, effective interest rate (as a percent)	4.25%
Long-term debt	$ 133,491	135,938
Revolving Credit Facility \| Revolver loan
Debt Instrument [Line Items]
Debt instrument, effective interest rate (as a percent)	4.25%
Long-term debt	$ 127,500	$ 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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