FAIR VALUE OF ASSETS AND LIABILITIES - SUCCESSOR COMPANY - Schedule of paid (Details) - Insurance liabilities $ in Millions	3 Months Ended
	Dec. 31, 2022 USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	$ 13,611
Reduction in estimates of ultimate losses	(8,095)
Increase in estimates of ultimate losses	1,936
Change in fair value (discount rate)	(2,266)
Paid losses	315
Other	45
Fair Value, end of period	5,546
Retained Business
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	3,362
Reduction in estimates of ultimate losses	(632)
Increase in estimates of ultimate losses	1,759
Change in fair value (discount rate)	(1,863)
Paid losses	282
Other	33
Fair Value, end of period	2,941
Ceded Business
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	10,249
Reduction in estimates of ultimate losses	(7,463)
Increase in estimates of ultimate losses	177
Change in fair value (discount rate)	(403)
Paid losses	33
Other	12
Fair Value, end of period	$ 2,605