Total Equity and Other Comprehensive Income (Dividends Per Share) (Details)			3 Months Ended		9 Months Ended
	Oct. 01, 2021 $ / shares	Sep. 13, 2021 $ / shares shares	Sep. 30, 2021 $ / shares shares	Sep. 30, 2020 $ / shares	Sep. 30, 2021 $ / shares shares	Sep. 30, 2020 $ / shares	Dec. 31, 2020 shares	Sep. 01, 2020 shares
Class of Stock [Line Items]
Depositary shares conversion ratio		0.01
Common stock held in treasury at cost (shares) | shares			120,000,000		120,000,000		119,000,000
Subsequent Event
Class of Stock [Line Items]
Cash dividends declared, common, per share (in dollars per share)	$ 1.25
Common Stock
Class of Stock [Line Items]
Cash dividends declared, common, per share (in dollars per share)			$ 1.25	$ 1.15	$ 3.55	$ 3.45
Series B
Class of Stock [Line Items]
Cash dividends declared, Preferred, per share (in dollars per share)			0.45	0.45	1.35	1.35
Series O
Class of Stock [Line Items]
Cash dividends declared, Preferred, per share (in dollars per share)			3,375	3,375	6,750	6,750
Series P
Class of Stock [Line Items]
Cash dividends declared, Preferred, per share (in dollars per share)			$ 1,531	1,531	4,594	4,594
Series Q
Class of Stock [Line Items]
Cash dividends declared, Preferred, per share (in dollars per share)				1,343		4,031
Treasury stock, preferred (shares) | shares								4,800
Common stock held in treasury at cost (shares) | shares								19,200,000
Series R
Class of Stock [Line Items]
Cash dividends declared, Preferred, per share (in dollars per share)					2,425	2,425
Series S
Class of Stock [Line Items]
Cash dividends declared, Preferred, per share (in dollars per share)					$ 2,500	$ 2,500
Depositary Shares
Class of Stock [Line Items]
Common stock held in treasury at cost (shares) | shares								19,200,000
Series T Preferred Stock
Class of Stock [Line Items]
Common stock activity (shares) | shares		1,500,000
Fixed interest rate		3.40%
Preferred stock, par or stated value per share (in dollars per share)		$ 1