Mortgage Servicing Rights - Effect of Hypothetical Changes in the Fair Value of MSRs (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Transfers and Servicing [Abstract]
Loans serviced	$ 1,494	$ 1,127	$ 1,124
Adverse change	(133)
Favorable change	99
Increase	(37)
Decrease	38
Increase	(41)
Decrease	44
Increase	(23)
Decrease	$ 6

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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