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Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	$ 52	$ 19	$ 6
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	128	$ 76
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	39
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$ 1,000
Federal [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date	Jan. 01, 2023
Open Tax Year	2017
Federal [Member] | Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date	Dec. 31, 2037
Open Tax Year	2020
State [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date	Jan. 01, 2021
Open Tax Year	2013
State [Member] | Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date	Dec. 31, 2040
Open Tax Year	2020
Non-U.S [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open Tax Year	2015
Non-U.S [Member] | Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Open Tax Year	2020
Finite-lived NOL carryforwards [Member] | Federal [Member]
Income Tax Contingency [Line Items]
Operating Loss Carryforwards	$ 100
Indefinite NOL carryforwards [Member] | Federal [Member]
Income Tax Contingency [Line Items]
Operating Loss Carryforwards	$ 309

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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