CORPORATE BORROWINGS - Indebtedness Outstanding Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt, gross	$ 40,000	$ 41,508
Unamortized loan fees	(129)	(448)
Total indebtedness outstanding, net	39,871	41,060
Less current maturities of long-term debt	(1,600)	(401)
Long-term debt	$ 38,271	40,659
Credit Agreement \| Revolver
Debt Instrument [Line Items]
Credit Agreement, interest rate	1.20%
Credit Agreement \| Revolver \| Revolving Credit Agreement, Due 2025
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	0
Credit Agreement, interest rate	1.15%
Credit Agreement \| Revolver \| Revolving Credit Agreement, Due 2022
Debt Instrument [Line Items]
Long-term debt, gross		$ 300
Credit Agreement, interest rate		3.19%
Senior Notes \| Secured Promissory Note
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	$ 1,208
Senior secured notes, stated interest rate		3.71%
Secured Debt \| Note Purchase Agreement Due 2027
Debt Instrument [Line Items]
Long-term debt, gross	$ 20,000	$ 20,000
Senior secured notes, stated interest rate	3.53%
Secured Debt \| Note Purchase Agreement Due 2029
Debt Instrument [Line Items]
Long-term debt, gross	$ 20,000	$ 20,000
Senior secured notes, stated interest rate	3.80%

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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