Supplemental financial information - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2020
Restructuring Cost and Reserve [Line Items]
Treasury shares issued related to stock compensation (in shares)	1,568,938	6,783,180
Severance and benefit costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 24
Restructuring payments		$ 0

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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