Consolidated Statements of Financial Position (Parentheticals) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Accumulated depreciation	$ 6,335	$ 5,850
Long-term Debt, Current Maturities	$ 742	$ 1,109
Preferred Stock, par value	$ 1	$ 1
Preferred Stock, shares authorized	10,000,000	10,000,000
Preferred Stock, shares issued	0	0
Preferred Stock, shares outstanding	0	0
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	800,000,000	800,000,000
Common stock, shares issued	166,717,179	167,848,424
Common stock, shares outstanding	166,717,179	167,848,424