Financing Receivables - Residential Mortgage Loans by Region (Details) - Consumer Loans - Residential mortgage loans - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2026	Dec. 31, 2025
Financing receivables - credit quality information
Loans	$ 905	$ 799
Total residential mortgage loans \| Credit concentration risk
Financing receivables - credit quality information
Percentage of total	100.00%	100.00%
Minnesota
Financing receivables - credit quality information
Loans	$ 438	$ 420
Minnesota \| Total residential mortgage loans \| Credit concentration risk
Financing receivables - credit quality information
Percentage of total	48.00%	53.00%
Other U.S. States
Financing receivables - credit quality information
Loans	$ 467	$ 379
Other U.S. States \| Total residential mortgage loans \| Credit concentration risk
Financing receivables - credit quality information
Percentage of total	52.00%	47.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details