Condensed Consolidated Statement of Shareholders' Investment (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Increase (Decrease) in Shareholders' Investment
Cash dividends declared per common share	$ 0.36	$ 0.32
Common Shares:
Increase (Decrease) in Shareholders' Investment
Balance at beginning of period (in shares)	1,976,855,085	1,971,189,465
Issued under incentive stock programs (in shares)	1,257,416	2,283,041
Balance at end of period (in shares)	1,978,112,501	1,973,472,506
Common Shares Held in Treasury:
Increase (Decrease) in Shareholders' Investment
Balance at beginning of period (in shares)	214,351,838	215,570,043
Issued under incentive stock programs (in shares)	5,333,626	6,544,927
Purchased (in shares)	248,963	266,128
Balance at end of period (in shares)	209,267,175	209,291,244