Taxes - Undistributed Foreign Earnings (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Taxes
Deferred tax liability for undistributed foreign earnings not indefinitely reinvested	$ 307	$ 725
Undistributed earnings of foreign subsidiaries indefinitely reinvested in foreign operations	$ 980

Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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