Shareholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 05, 2018
Class of Stock [Line Items]
Authorized capital stock, common stock (shares)	500,000,000
Common stock, par value (in dollars per share)	$ 1
Authorized capital stock, preferred stock (shares)	50,000,000
Preferred stock, par value (in dollars per share)	$ 1
Common stock, issued (shares)	481,880,634	481,880,634
Common stock, outstanding (shares)	277,620,943	286,477,836
Preferred stock, outstanding (shares)	0	0
Share repurchased, additional amount authorized (shares)				10,000,000
Stock repurchased (shares)	10,300,000	4,100,000	1,100,000
Shares repurchased	$ 1,835	$ 602	$ 184
Shares remaining under a prior authorization	12,100,000
Percent of total shares outstanding authorized for repurchase	4.30%
Dividends declared per share	$ 4.76	$ 4.40	$ 4.08
Dividends paid	$ 1,315	$ 1,240	$ 1,152
Restricted Stock
Class of Stock [Line Items]
Unvested restricted stock (shares)	532,142