Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Earnings Per Share [Abstract]
Net income	$ 1,429	$ 1,826
Less:
Net income attributable to noncontrolling interests	21	10
Preferred stock dividends	45	57
Preferred stock discount accretion and redemptions	2	1
Net income attributable to common shareholders	1,361	1,758
Less: Dividends and undistributed earnings allocated to nonvested restricted shares	6	8
Net income attributable to basic common shareholders	$ 1,355	$ 1,750
Basic weighted-average common shares outstanding (in shares)	420	426
Basic earnings per common share (in dollars per share)	$ 3.23	$ 4.11
Net income attributable to diluted common shareholders	$ 1,355	$ 1,750
Diluted (in shares)	420	426
Diluted earnings per common share (in dollars per share)	$ 3.23	$ 4.10