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		9 Months Ended
	Sep. 30, 2020	Jun. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Foreign Currency Translation
Foreign currency transaction loss	$ 15		$ 4
Venezuela
Foreign Currency Translation
Loss on deconsolidation of Venezuelan subsidiary		$ 162		$ 162
Foreign currency transaction loss		$ 144