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LONG-TERM OBLIGATIONS (Details) - USD ($) $ in Thousands	6 Months Ended
LONG-TERM OBLIGATIONS (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Line of Credit Facility [Line Items]
Cash and temporary investments	$ 30,502	$ 40,153	$ 31,129	$ 54,332
First Tennessee Bank National Association \| Credit facility
Line of Credit Facility [Line Items]
Revolving credit facility	100,000
Line of credit outstanding borrowings	$ 60
First Tennessee Bank National Association \| Credit facility \| Minimum \| Secured Overnight Financing Rate (SOFR) [Member]
Line of Credit Facility [Line Items]
Variable interest rate in addition to reference rate	1.00%
Non-usage fee for current loan agreement in annual amount percentage	0.15%
First Tennessee Bank National Association \| Credit facility \| Maximum \| Secured Overnight Financing Rate (SOFR) [Member]
Line of Credit Facility [Line Items]
Variable interest rate in addition to reference rate	1.25%
Non-usage fee for current loan agreement in annual amount percentage	0.35%