CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Statement of Comprehensive Income [Abstract]
Net Income	$ 573	$ 660	$ 1,694	$ 1,819
Net unrealized losses on available-for-sale debt securities:
Unrealized holding gains (losses) arising during period	944	(1,218)	763	(1,252)
Unrealized losses on available-for-sale debt securities transferred to held-to-maturity securities	0	0	785	0
Reclassification adjustment for net losses included in net income	9	0	13	1
Net unrealized losses on available-for-sale debt securities transferred to held-to-maturity securities:
Unrealized losses on available-for-sale debt securities transferred to held-to-maturity securities	0	0	(785)	0
Amortization of unrealized losses on available-for-sale debt securities transferred to held-to-maturity securities	26	0	76	0
Net unrealized losses on cash flow hedge derivatives:
Unrealized holding (losses) gains arising during period	403	(527)	(22)	(664)
Reclassification adjustment for net losses included in net income	70	72	208	185
Defined benefit pension plans, net:
Reclassification of amounts to net periodic benefit costs	1	0	1	1
Other	2	0	2	0
Other comprehensive income (loss), net of tax	1,455	(1,673)	1,041	(1,729)
Comprehensive Income (Loss)	$ 2,028	$ (1,013)	$ 2,735	$ 90