Accumulated Other Comprehensive Loss - Schedule of Reclassification Out of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before tax	$ 56	$ (26)	$ 924	$ (252)
Other comprehensive income (loss), tax effect	(13)	6	(219)	59
Other comprehensive (loss) income, net of tax	43	(20)	705	(193)
Available-for-sale securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net unrealized gains (losses) arising during the period, before tax	26		372	(270)
Net unrealized gains (losses) arising during the period, tax	(7)		(88)	64
Net unrealized gains (losses) arising during the period, net of tax	19		284	(206)
Reclassification from AOCI, before tax	2		(493)	1
Reclassification from AOCI, tax	(1)		117	0
Reclassification from AOCI, net of tax	1		(376)	1
Other comprehensive income (loss), before tax	24	(47)	865	(271)
Other comprehensive income (loss), tax effect	(6)	11	(205)	64
Other comprehensive (loss) income, net of tax	18	(36)	660	(207)
Held-to-maturity securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, before tax	(22)	(22)	(42)	(42)
Reclassification from AOCI, tax	5	5	10	10
Reclassification from AOCI, net of tax	(17)	(17)	(32)	(32)
Other comprehensive (loss) income, net of tax	17	17	32	32
Translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before tax	12	(2)	12	(7)
Other comprehensive income (loss), tax effect	(3)	0	(3)	1
Other comprehensive (loss) income, net of tax	9	(2)	9	(6)
Net investment hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before tax	(9)	2	(9)	6
Other comprehensive income (loss), tax effect	2	0	2	(1)
Other comprehensive (loss) income, net of tax	(7)	2	(7)	5
Cash flow hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net unrealized gains (losses) arising during the period, before tax	(1)	(3)	(1)	(25)
Net unrealized gains (losses) arising during the period, tax	0	1	0	6
Net unrealized gains (losses) arising during the period, net of tax	(1)	(2)	(1)	(19)
Reclassification from AOCI, before tax	(8)	(2)	(15)	(3)
Reclassification from AOCI, tax	1	1	3	1
Reclassification from AOCI, net of tax	(7)	(1)	(12)	(2)
Other comprehensive income (loss), before tax	7	(1)	14	(22)
Other comprehensive income (loss), tax effect	(1)	0	(3)	5
Other comprehensive (loss) income, net of tax	$ 6	$ (1)	$ 11	$ (17)