v3.26.3
Revenue from contracts with customers - Schedule of Sales Reserves and Allowances (Detail) - USD ($)
$ in Millions
 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]    
Balance at beginning of period $ 4,206 $ 3,734
Provisions related to sales made in current year period 10,906 11,154
Provisions related to sales made in prior periods (142) (48)
Credits and payments (10,914) (10,751)
Translation differences (39) 116
Balance at end of period 4,017 4,205
Reserves included in Accounts Receivable, net    
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]    
Balance at beginning of period 63 56
Provisions related to sales made in current year period 287 310
Provisions related to sales made in prior periods 0 0
Credits and payments (288) (295)
Translation differences 0 0
Balance at end of period 62 71
Total reserves included in Sales Reserves and Allowances    
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]    
Balance at beginning of period 4,143 3,678
Provisions related to sales made in current year period 10,619 10,844
Provisions related to sales made in prior periods (142) (48)
Credits and payments (10,626) (10,456)
Translation differences (39) 116
Balance at end of period 3,955 4,134
Rebates    
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]    
Balance at beginning of period 1,954 1,674
Provisions related to sales made in current year period 3,619 3,746
Provisions related to sales made in prior periods (78) (38)
Credits and payments (3,606) (3,432)
Translation differences (24) 61
Balance at end of period 1,865 2,011
Medicaid and other governmental allowances    
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]    
Balance at beginning of period 701 561
Provisions related to sales made in current year period 926 753
Provisions related to sales made in prior periods (32) 33
Credits and payments (874) (701)
Translation differences (4) 16
Balance at end of period 717 662
Chargebacks    
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]    
Balance at beginning of period 937 936
Provisions related to sales made in current year period 5,823 6,012
Provisions related to sales made in prior periods (6) (29)
Credits and payments (5,888) (6,062)
Translation differences (5) 18
Balance at end of period 861 875
Returns    
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]    
Balance at beginning of period 445 399
Provisions related to sales made in current year period 203 213
Provisions related to sales made in prior periods (23) (3)
Credits and payments (226) (168)
Translation differences (2) 5
Balance at end of period 397 446
Other    
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]    
Balance at beginning of period 106 108
Provisions related to sales made in current year period 48 120
Provisions related to sales made in prior periods (3) (11)
Credits and payments (32) (93)
Translation differences (4) 16
Balance at end of period $ 115 $ 140