Derivative instruments - (Fair Value of Derivatives) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Assets
Total derivative assets, fair value	$ 265	$ 349
Liabilities
Total derivative liabilities, fair value	534	570
Derivatives designated as hedging instruments [Member]
Assets
Total derivative assets, fair value	265	349
Liabilities
Total derivative liabilities, fair value	534	570
Derivatives designated as hedging instruments [Member] | Foreign currency contracts [Member] | Other current assets/Other assets [Member]
Assets
Total derivative assets, fair value	183	28
Derivatives designated as hedging instruments [Member] | Foreign currency contracts [Member] | Accrued liabilities/Other noncurrent liabilities [Member]
Liabilities
Total derivative liabilities, fair value	39	237
Derivatives designated as hedging instruments [Member] | Cross-currency swap contracts [Member] | Other current assets/Other assets [Member]
Assets
Total derivative assets, fair value	66	255
Derivatives designated as hedging instruments [Member] | Cross-currency swap contracts [Member] | Accrued liabilities/Other noncurrent liabilities [Member]
Liabilities
Total derivative liabilities, fair value	339	318
Derivatives designated as hedging instruments [Member] | Interest rate swap contracts [Member] | Other current assets/Other assets [Member]
Assets
Total derivative assets, fair value	16	66
Derivatives designated as hedging instruments [Member] | Interest rate swap contracts [Member] | Accrued liabilities/Other noncurrent liabilities [Member]
Liabilities
Total derivative liabilities, fair value	$ 156	$ 15