MORTGAGE LOANS RECEIVABLE - Summary of the Geographic Distribution of Mortgage Loans Receivable (Details) - Mortgage Loans Receivable - Geographic Concentration Risk - Loan Origination Commitments	12 Months Ended
Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Loan Commitment	100.00%
California
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Loan Commitment	58.90%
Washington
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Loan Commitment	12.20%
New York
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Loan Commitment	5.60%
Other U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Total Loan Commitment	23.30%

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e9054-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13531-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13537-108611

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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