NOTES PAYABLE AND AMENDED CREDIT AGREEMENT - Summary of Notes Payable and Credit Agreement (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Debt Instruments [Abstract]
Payments/Long term debt	$ 21,650	$ 21,495
Less current portion	(5,079)	(4,899)
Long term portion	16,571	16,596
Credit Facility [Member]
Debt Instruments [Abstract]
Payments/Long term debt	$ 16,000	$ 16,000
Average effective interest rate	3.00%	2.60%
3.25% through 5.50% Notes Payable due in Next Year [Member]
Debt Instruments [Abstract]
Payments/Long term debt	$ 5,650	$ 5,495
Annual installments	$ 5,079
3.25% through 5.50% Notes Payable due in Next Year [Member] \| Minimum [Member]
Debt Instruments [Abstract]
Percentage of interest accrued	3.25%
3.25% through 5.50% Notes Payable due in Next Year [Member] \| Maximum [Member]
Debt Instruments [Abstract]
Percentage of interest accrued	5.50%

Amount of the total principal payments made during the annual reporting period.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The effective interest rate during the reporting period.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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