Expected Loss to be Paid (Recovered) - Net Expected Loss to be Paid (Recovered) Roll Forward (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward]
Net expected loss to be paid (recovered), beginning of period	$ 411	$ 529	$ 737
Accretion of discount	16	7	9
Changes in discount rates	(115)	(33)	13
Changes in timing and assumptions	(26)	(261)	123
Total economic loss development (benefit)	(125)	(287)	145
Net (paid) recovered losses	236	169	(353)
Net expected loss to be paid (recovered), end of period	$ 522	$ 411	$ 529
Weighted average risk free discount rate	4.08%	1.02%
U.S.
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward]
Percent of total non-U.S. net expected losses to paid	98.50%	97.20%
Minimum
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward]
Risk free discount rate	3.82%	0.00%
Maximum
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward]
Risk free discount rate	4.69%	1.98%