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Expected Loss to be Paid (Recovered) - Net Economic Loss Development (Benefit) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Schedule of Expected Losses to be Paid [Line Items]
RMBS losses	$ (32)	$ (20)	$ (76)	$ (7)
RMBS | United States
Schedule of Expected Losses to be Paid [Line Items]
RMBS losses	(39)	(28)	(32)	(17)
RMBS | United States | First Lien
Schedule of Expected Losses to be Paid [Line Items]
RMBS losses	(14)	(14)	4	11
RMBS | United States | Second Lien
Schedule of Expected Losses to be Paid [Line Items]
RMBS losses	$ (25)	$ (14)	$ (36)	$ (28)

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