Segment Reporting Other Items (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation and Amortization			$ 1,599	$ 2,790
Investments in nonconsolidated affiliates		$ 66	66
Payments to Acquire Property, Plant, and Equipment			1,163	1,501
Operating Segments [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation and Amortization		1,177	1,000	909
Investments in nonconsolidated affiliates		66	66	138
Payments to Acquire Property, Plant, and Equipment		$ 475	666	513
Discontinued Operations [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation and Amortization	[1]		599	1,881
Payments to Acquire Property, Plant, and Equipment	[1]		$ 497	$ 988

[1] See Note 5 - Divestitures and Other Transactions, to the Consolidated Financial Statements, for additional information