Financial Instruments Cross-currency interest rate swap contracts (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Cross-currency interest rate swap contracts \| Derivatives Designated as Hedging Instruments:
Foreign Currency Fair Value Hedge Derivative [Line Items]
Gain (Loss) on Components Excluded from Assessment of Interest Rate Fair Value Hedge Effectiveness	$ 3	$ 4	$ 9	$ 14

The net gain (loss) included in earnings for the period relating to components of the gain (loss) on interest rate fair value hedging instruments excluded from the assessment of fair value hedge effectiveness.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=121577467&loc=d3e76258-113986

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