Consolidated Statements Of Financial Position (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Other assets, accumulated amortization	$ 482	$ 497
Common stock, par value	$ 5.00	$ 5.00
Common stock, authorized	1,200,000,000	1,200,000,000
Common stock, shares issued	1,012,261,159.000000	1,012,261,159.000000