LONG-TERM DEBT - Schedule of Borrowing Capacity and Amount Borrowed (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Mar. 19, 2019
Amount Borrowed	$ 234,457	$ 234,457
First Lien Revolving Facility [Member]
Borrowing Capacity	20,000		$ 20,000
Amount Borrowed	$ 7,000	$ 7,000

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant