Amount of contractually specified servicing fee, late fee, and ancillary fee recognized as income for servicing asset and servicing liability.

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Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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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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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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Servicing of Financial Assets (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Servicing Assets at Fair Value [Line Items]
Servicing Asset at Fair Value, Amount	$ 1,026		$ 906
Residential Mortgage [Member]
Servicing Assets at Fair Value [Line Items]
Servicing related fees and other ancillary income	44	$ 38
Servicing Asset at Fair Value, Amount	1,026	790	906	$ 812
Fannie Mae DUS License [Member]
Servicing Assets at Fair Value [Line Items]
Servicing Asset at Amortized Cost	85		87
Servicing Asset at Fair Value, Amount	112		$ 109	$ 109
Commercial Real Estate [Member]
Servicing Assets at Fair Value [Line Items]
Servicing related fees and other ancillary income	$ 5	$ 5