Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Finite-Lived Intangible Assets
Gross Carrying Amount	$ 353	$ 361
Accumulated Amortization	(255)	(236)
Net Carrying Amount	98	125
Core deposit intangibles
Finite-Lived Intangible Assets
Gross Carrying Amount	206	209
Accumulated Amortization	(192)	(184)
Net Carrying Amount	14	25
Developed technology
Finite-Lived Intangible Assets
Gross Carrying Amount	106	106
Accumulated Amortization	(46)	(33)
Net Carrying Amount	60	73
Customer relationships
Finite-Lived Intangible Assets
Gross Carrying Amount	28	30
Accumulated Amortization	(9)	(10)
Net Carrying Amount	19	20
Other
Finite-Lived Intangible Assets
Gross Carrying Amount	13	16
Accumulated Amortization	(8)	(9)
Net Carrying Amount	$ 5	$ 7