Contingencies and commitments (U.S. Repatriation Tax Commitments) (Details) $ in Millions	Dec. 31, 2021 USD ($) installment
Commitments and Contingencies Disclosure [Abstract]
U.S. repatriation tax commitments, number of annual installments \| installment	8
U.S. repatriation tax commitments, 2022	$ 587
U.S. repatriation tax commitments, 2023	1,100
U.S. repatriation tax commitments, 2024	1,467
U.S. repatriation tax commitments, 2025	1,834
Total remaining U.S. repatriation tax commitments	$ 4,988

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