COMMERCIAL MORTGAGE LOANS - Schedule of Allowance for Credit Losses on Funded and Unfunded Mortgages (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020
Allowance for Funded Commercial Mortgage Loan Credit Losses
Beginning balance	$ 173,186	$ 4,884
Charge offs	0	0
Recoveries	0	(1,839)
Provision	1,864	91,766
Ending balance	175,050	175,050
Allowance for Unfunded Commercial Mortgage Loan Commitments Credit Losses
Beginning balance	19,550	0
Charge offs	0	0
Recoveries	0	0
Provision	247	9,187
Ending balance	19,797	19,797
Cumulative Effect Adjustment
Allowance for Funded Commercial Mortgage Loan Credit Losses
Beginning balance	0	80,239
Allowance for Unfunded Commercial Mortgage Loan Commitments Credit Losses
Beginning balance	$ 0	$ 10,610

Off-Balance Sheet, Credit Loss, Liability, Recovery

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Off-Balance Sheet, Credit Loss, Liability, Writeoffs

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The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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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 of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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