CONSOLIDATED BALANCE SHEET (Parenthetical) - $ / shares	Dec. 31, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Common shares, par value	$ 1.25	$ 1.25
Common shares, authorized	1,360,000,000	1,360,000,000
Common shares, issued	745,300,000	746,391,000
Common shares, outstanding	745,300,000	746,391,000