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Expected Loss to be Paid (Recovered) - Net Economic Loss Development (Benefit) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Schedule of Expected Losses to be Paid [Line Items]
RMBS losses	$ (72)	$ (94)	$ (148)	$ (101)
RMBS | United States
Schedule of Expected Losses to be Paid [Line Items]
RMBS losses	(95)	(65)	(127)	(82)
RMBS | United States | First Lien
Schedule of Expected Losses to be Paid [Line Items]
RMBS losses	(38)	(10)	(34)	1
RMBS | United States | Second Lien
Schedule of Expected Losses to be Paid [Line Items]
RMBS losses	$ (57)	$ (55)	$ (93)	$ (83)

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