BORROWED FUNDS - Senior Notes (Details) - USD ($)		3 Months Ended	6 Months Ended
May 19, 2021	Jun. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Senior notes, net		$ 14,670,000	$ 14,670,000	$ 0
Agreements with an aggregate par value of $15,000,000; bearing interest at 2.75%; maturing in June 2031 and redeemable at par in June 2026
Debt Instrument [Line Items]
Aggregate par value	$ 15,000,000.0	$ 15,000,000	$ 15,000,000	$ 15,000,000
Stated interest rate	2.75%	2.75%	2.75%	2.75%
Debt issuance costs	$ 337,000
Senior notes, net	$ 14,663,000	$ 14,670,000	$ 14,670,000	$ 0
Amortization of debt issuance costs		$ 7,000	$ 7,000
Effective interest rate		3.23%	3.23%	3.23%

Face (par) amount of debt instrument at time of issuance.

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

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Amount of expense for amortization of deferred issuance costs associated with an own-share lending arrangement.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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