INVESTMENTS - Realized Gains (Losses) on Investments (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	9 Months Ended
Mar. 31, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Debt Securities, Available-for-Sale [Line Items]
Proceeds from maturities/prepayments	$ 422		$ 0	$ 8,859
Fixed Maturities
Debt Securities, Available-for-Sale [Line Items]
Proceeds from sales		$ 216		8,009
Proceeds from maturities/prepayments		196		607
Gross investment gains on sales and maturities		157		1,296
Gross investment losses on sales and maturities		(14)		(75)
Write-downs recognized in earnings		0		(23)
(Addition to) release of allowance for credit losses		$ (2)		(2)
Noncash related proceeds				$ (243)

Debt Securities, Available-For-Sale, Recognized In Earnings

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Amount of increase (decrease) in allowance for credit loss of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of noncash consideration received for selling an asset or business through a noncash (or part noncash) transaction.

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Amount of cash inflow from maturity, prepayment and call of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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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