Sales of Receivables and Servicing Rights - Activity Related to the MSR Portfolio (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Transfers and Servicing [Abstract]
Changes in fair value and settlement of free-standing derivatives purchased to economically hedge the MSR portfolio	$ 45	$ (75)	$ (17)	$ (110)
MSR fair value adjustment due to changes in inputs or assumptions	$ (49)	$ 73	$ 1	$ 107