Income Taxes, Liability for Unrecognized Tax Benefits Recognized in Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Amounts Recognized in Balance Sheets for Uncertain Tax Positions
Other long-term liabilities and Deferred tax liabilities	$ 954	$ 721
Liability for unrecognized tax benefits presented in our balance sheets	968	781
Income Taxes Payable [Member]
Amounts Recognized in Balance Sheets for Uncertain Tax Positions
Income taxes payable	0	42
Other Long-term Liabilities [Member]
Amounts Recognized in Balance Sheets for Uncertain Tax Positions
Other long-term liabilities and Deferred tax liabilities	954	721
Deferred Tax Liabilities[Member]
Amounts Recognized in Balance Sheets for Uncertain Tax Positions
Other long-term liabilities and Deferred tax liabilities	$ 14	$ 18