Property, Plant and Equipment (Depreciation Expense, Software Amortization and Capitalized Interest) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 972	$ 1,004	$ 977
Interest capitalized during development and construction	226	307	$ 238
Property plant and equipment, net of accumulated depreciation mortgaged, pledged or subject to liens	$ 9,000	$ 10,000