INVESTMENTS - Mortgage Loans (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	$ 277
Balance, end of period	293	$ 139
Commercial mortgages:
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	270	123
Current-period provision for expected credit losses	14	10
Write-offs charged against the allowance	0	0
Recoveries of amounts previously written off	0	0
Net change in allowance	14	10
Balance, end of period	284	133
Agricultural mortgages:
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	6	6
Current-period provision for expected credit losses	0	0
Write-offs charged against the allowance	0	0
Recoveries of amounts previously written off	0	0
Net change in allowance	0	0
Balance, end of period	6	6
Residential mortgages:
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	1	0
Current-period provision for expected credit losses	2	0
Write-offs charged against the allowance	0	0
Recoveries of amounts previously written off	0	0
Net change in allowance	2	0
Balance, end of period	$ 3	$ 0