Guarantor Obligations, Net Expected Loss Development After Recoveries for Representations and Warranties

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- Definition

Guarantor Obligations, Net Expected Loss Development After Recoveries for Representations and Warranties, Changes In Discount Rates

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Guarantor Obligations, Net Expected Loss to be Paid After Recoveries for Representations and Warranties, Discount Rate

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- Definition

Guarantor Obligations, Net Expected Loss to be Paid After Recoveries for Representations and Warranties, Weighted Average Discount Rate

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- Definition

Guarantor Obligations, Net Expected Loss to be Paid After Recoveries for Representations and Warranties

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- Definition

Guarantor Obligations, Projected Loss Assumption, Deferred Loan Balances to be Recovered, Percent

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[Line Items] for Schedule of Expected Losses to be Paid [Table]

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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		12 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2024
Schedule of Expected Losses to be Paid [Line Items]
Net Expected Loss to be Paid (Recovered)	$ 192	$ 186	$ 192	$ 186	$ 101	$ 141	$ 150	$ 106
RMBS losses	48	36	92	21
Changes in discount rates	(2)	1	(6)	6
RMBS \| United States
Schedule of Expected Losses to be Paid [Line Items]
Net Expected Loss to be Paid (Recovered)	(40)	(35)	(40)	(35)	$ (54)	$ (48)	$ (37)	$ (43)
RMBS losses	(1)	(6)	(3)	(9)
Changes in discount rates	$ 0	(2)	$ 0	(1)
Weighted average discount rate	4.31%		4.31%		3.84%
RMBS \| United States \| Minimum
Schedule of Expected Losses to be Paid [Line Items]
Range of discount rates	3.62%		3.62%		3.45%
RMBS \| United States \| Maximum
Schedule of Expected Losses to be Paid [Line Items]
Range of discount rates	5.07%		5.07%		4.97%
RMBS \| United States \| First Lien
Schedule of Expected Losses to be Paid [Line Items]
Net Expected Loss to be Paid (Recovered)	$ 92		$ 92		$ 90
RMBS losses	0	(4)	$ 0	(2)
RMBS \| United States \| First Lien \| Weighted Average \| Base Scenario
Schedule of Expected Losses to be Paid [Line Items]
Percent of deferred loan balances to be recovered			50.00%		50.00%
RMBS \| United States \| Second Lien
Schedule of Expected Losses to be Paid [Line Items]
Net Expected Loss to be Paid (Recovered)	(132)		$ (132)		$ (144)
RMBS losses	$ (1)	$ (2)	$ (3)	$ (7)
Percent of deferred loan balances to be recovered			2.00%
RMBS \| United States \| Second Lien \| Weighted Average \| Base Scenario
Schedule of Expected Losses to be Paid [Line Items]
Percent of deferred loan balances to be recovered			60.00%		60.00%