FAIR VALUE MEASUREMENTS - Fair Value of Derivatives (Details)	9 Months Ended
Sep. 30, 2021 USD ($) item	Dec. 31, 2020 USD ($)
Interest rate derivatives
FAIR VALUE MEASUREMENTS
Number of mortgage loans outstanding \| item	20
Interest rate derivatives \| Cash flow hedges
FAIR VALUE MEASUREMENTS
Number of interest rate derivatives held \| item	20
Notional Amount \| $	$ 61,360,000
Weighted average maturity	2 years 7 months 6 days
Weighted average annual interest rate (as a percent)	4.09%
Interest rate derivatives \| Cash flow hedges \| Minimum
FAIR VALUE MEASUREMENTS
Fixed interest rate (as a percent)	3.02%
Interest rate derivatives \| Cash flow hedges \| Maximum
FAIR VALUE MEASUREMENTS
Fixed interest rate (as a percent)	5.16%
Recurring \| Interest rate swap \| Level 2 \| Other liabilities
Financial liabilities:
Derivative financial instruments \| $	$ 2,352,000	$ 5,012,000

The number of mortgage loans outstanding with related interest rate derivatives.

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- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

No definition available.

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Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

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- Definition

Nominal or face amount used to calculate payment on derivative.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

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