Significant Accounting Policies - Foreign Currency Translation (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Jun. 30, 2019
Foreign Currency Translation
Foreign currency transaction loss	$ 1
Venezuela
Foreign Currency Translation
Loss on deconsolidation of Venezuelan subsidiary		$ 162
Foreign currency transaction loss		$ 144

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Period Type:	duration