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		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Servicing Assets at Fair Value [Line Items]
Residential mortgage servicing rights at fair value	$ 801		$ 801			$ 812
Residential Mortgage [Member]
Servicing Assets at Fair Value [Line Items]
Servicing related fees and other ancillary income	39	$ 28	77	$ 55
Residential mortgage servicing rights at fair value	801	770	801	770	$ 790	812	$ 542	$ 418
Fannie Mae DUS License [Member]
Servicing Assets at Fair Value [Line Items]
Servicing Asset at Amortized Cost	78		78			81
Residential mortgage servicing rights at fair value	101		101			$ 96
Commercial Real Estate [Member]
Servicing Assets at Fair Value [Line Items]
Servicing related fees and other ancillary income	$ 6	$ 7	$ 11	$ 14