Expected Loss to be Paid (Recovered) - Net Economic Loss Development (Benefit) U.S. RMBS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Schedule of Expected Losses to be Paid [Line Items]
Net Economic Loss Development (Benefit)	$ 164	$ (125)	$ (287)
U.S. | RMBS
Schedule of Expected Losses to be Paid [Line Items]
Net Economic Loss Development (Benefit)	(56)	(143)	(100)
First Lien | U.S. | RMBS
Schedule of Expected Losses to be Paid [Line Items]
Net Economic Loss Development (Benefit)	7	(36)	0
Second Lien | U.S. | RMBS
Schedule of Expected Losses to be Paid [Line Items]
Net Economic Loss Development (Benefit)	$ (49)	$ (107)	$ (100)