Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Fixed assets, accumulated depreciation and amortization	$ 2,317	$ 2,159
Preferred stock, par value (usd per share)	$ 1	$ 1
Preferred stock, shares authorized	6,000,000	6,000,000
Preferred stock, shares issued	0	0
Common stock, par value (usd per share)	$ 1	$ 1
Common stock, shares authorized	1,600,000,000	1,600,000,000
Common stock, shares issued	560,641,640	560,641,640
Treasury shares, shares	53,676,347	52,914,550

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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