Earnings Per Common Share (EPS) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Basic and diluted:
Net income		$ 2,437	$ 1,816
Preferred dividends		(14)	(14)
Net income available to common shareholders		2,423	1,802
Earnings allocated to participating share awards		(18)	(14)
Net income attributable to common shareholders		$ 2,405	$ 1,788
Denominator:
Basic: Weighted-average common stock (in shares)		721.0	743.0
Add: Weighted-average stock options (in shares)		1.0	1.0
Diluted (in shares)		722.0	744.0
Basic EPS (in dollars per share)	[1]	$ 3.34	$ 2.41
Diluted EPS (in dollars per share)	[1]	$ 3.33	$ 2.40
Stock Option
Denominator:
The dilutive effect of securities excluded from the calculation of earnings per share (in shares)		0.1	1.3

[1] Represents net income less (i) earnings allocated to participating share awards of $18 million and $14 million for the three months ended March 31, 2024 and 2023, respectively, and (ii) dividends on preferred shares of $14 million for both the three months ended March 31, 2024 and 2023.