MORTGAGE LOAN RECEIVABLES - Activity in Loan Portfolio (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Jan. 01, 2020
Mortgage loan receivables held for investment, net, at amortized cost:
Mortgage loans receivable, beginning balance	$ 3,521,985	$ 2,343,070	$ 3,358,861
Origination of mortgage loan receivables	1,296,083	2,530,247	566,506
Purchases of mortgage loan receivables	0
Repayment of mortgage loan receivables	(901,150)	(1,059,979)	(961,236)
Proceeds from sales of mortgage loan receivables	(29,151)	(305,649)	(582,764)
Non-cash disposition of loans via foreclosure	(10,235)	(81,289)	(31,249)
Sale of loans, net	(2,511)	8,398	(1,571)
Accretion/amortization of discount, premium and other fees	20,759	13,832	15,530
Allowance for credit losses				$ (11,600)
Mortgage loans receivable, ending balance	3,892,382	3,521,985	2,343,070
Allowance for credit losses
Beginning balance, Allowance for credit losses	(31,752)	(41,507)	(20,500)
Charge-offs	14,395	0	0
Provision expense for current expected credit loss (implementation impact)			(4,964)
Provision expense for current expected credit loss (impact to earnings)	(3,398)	8,605	(18,543)
Release (addition) of provision for current expected credit loss, net	(3,711)	8,713	(18,275)
Ending balance, Allowance for credit losses	(20,755)	(31,752)	(41,507)
Total mortgage loans receivable
Mortgage loan receivables held for investment, net, at amortized cost:
Mortgage loans receivable, beginning balance	3,553,737	2,354,059
Mortgage loans receivable, ending balance	3,885,746	3,553,737	2,354,059
Total mortgage loan receivables held for investment, net, at amortized cost
Mortgage loan receivables held for investment, net, at amortized cost:
Mortgage loans receivable, beginning balance	3,553,737	2,354,059	3,257,036
Origination of mortgage loan receivables	1,234,765	2,309,888	353,661
Purchases of mortgage loan receivables	0	63,600
Repayment of mortgage loan receivables	(901,082)	(1,059,796)	(960,832)
Proceeds from sales of mortgage loan receivables	0	(46,557)	(270,491)
Non-cash disposition of loans via foreclosure	(10,235)	(81,289)	(31,249)
Sale of loans, net	2,197	0	(9,596)
Accretion/amortization of discount, premium and other fees	20,759	13,832	15,530
Charge offs	(14,395)
Mortgage loans receivable, ending balance	3,885,746	3,553,737	2,354,059
Allowance for credit losses
Beginning balance, Allowance for credit losses	(31,752)	(41,507)	(20,500)
Charge-offs	14,395
Release of asset-specific loan loss provision via foreclosure		1,150	2,500
Provision expense for current expected credit loss (implementation impact)			(4,964)
Provision expense for current expected credit loss (impact to earnings)	(3,398)	8,605	(18,543)
Release (addition) of provision for current expected credit loss, net		8,605
Ending balance, Allowance for credit losses	(20,755)	(31,752)	(41,507)
Mortgage loan receivables held for sale
Mortgage loan receivables held for investment, net, at amortized cost:
Mortgage loans receivable, beginning balance	0	30,518	122,325
Origination of mortgage loan receivables	61,318	220,359	212,845
Purchases of mortgage loan receivables	0	0
Repayment of mortgage loan receivables	(68)	(183)	(404)
Proceeds from sales of mortgage loan receivables	(29,151)	(259,092)	(312,273)
Non-cash disposition of loans via foreclosure		0	0
Sale of loans, net	(4,708)	8,398	8,025
Accretion/amortization of discount, premium and other fees		0	0
Charge offs	0
Mortgage loans receivable, ending balance	$ 27,391	$ 0	$ 30,518

Financing Receivable, Allowance for Credit Losses, Effect of Change in Method, Implementation Impact

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Financing Receivable, Excluding Accrued Interest, Credit Loss, Expense (Reversal), Release Of Asset-Specific Loan Loss Provision

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Represents the amount of accretion/ amortization of discount, premium and other fees on mortgage loans on real estate accreted/ amortized during the reporting period.

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Mortgage Loans on Real Estate, Financing Receivable, Excluding Accrued Interest, Allowance For Credit Loss, Writeoff

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Mortgage Loans on Real Estate, Purchases of Mortgage Loans

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Amount of decrease in investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from collection of principal.

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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Amount of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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Amount of decrease in investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from sale.

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Amount of increase in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from new investment.

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Amount of expense related to estimated loss from loan and lease transactions.

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