Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Significant Accounting Policies - Foreign Currency Translation (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2019
Foreign Currency
Loss on deconsolidation of Venezuelan subsidiary			$ 162
Foreign currency transaction loss		$ 21	$ (201)
Venezuela
Foreign Currency
Loss on deconsolidation of Venezuelan subsidiary	$ 162
Foreign currency transaction loss	$ 144