Condensed Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Condensed Consolidated Balance Sheet
Trade receivables, allowances (in dollars)	$ 507	$ 460
Preferred shares, par value (in dollars per share)	$ 1	$ 1
Preferred shares, authorized shares	1,000,000	1,000,000
Preferred shares, issued shares	0	0
Common shares, authorized shares	2,400,000,000	2,400,000,000
Common shares, issued shares	1,983,103,854	1,981,156,896
Common shares held in treasury, shares	214,816,885	209,926,622