BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Leases (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020
Lessor, Lease, Description [Line Items]
Reduction in revenue	$ 136	$ 47	$ 538
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract]
2021 (remainder)	593	593
2022	2,339	2,339
2023	2,336	2,336
2024	2,323	2,323
2025	2,292	2,292
Thereafter	2,488	2,488
Total scheduled lease income - commercial operating leases	$ 12,371	$ 12,371
Minimum
Lessor, Lease, Description [Line Items]
Lease terms	3 years	3 years
Maximum
Lessor, Lease, Description [Line Items]
Lease terms	15 years	15 years
Rental Income \| Revenue \| Product Concentration Risk
Lessor, Lease, Description [Line Items]
Concentration risk		98.10%
Fee Income \| Revenue \| Product Concentration Risk
Lessor, Lease, Description [Line Items]
Concentration risk		1.90%

Lessor, Operating Lease, Payment to be Received, after Year Four

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Revenue Reduction Due To Rental Abatements, Amount

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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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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No definition available.

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Amount of lease payments to be received by lessor for operating lease.

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Amount of lease payment to be received by lessor for operating lease in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lease payment to be received by lessor for operating lease in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lease payment to be received by lessor for operating lease in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lease payment to be received by lessor for operating lease in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lease payment to be received by lessor for operating lease in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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