Financing arrangements (Details Textual) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)
Notes [Member]
Debt Instrument [Line Items]
Face amount	$ 5,000	$ 5,000
Notes [Member] \| 4.563% notes due 2048 (4.563% 2048 Notes) [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	4.563%	4.563%
Effective interest rate	6.30%	6.30%
Notes [Member] \| 4.663% notes due 2051 (4.663% 2051 Notes) [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	4.663%	4.663%
Effective interest rate	5.60%	5.60%
Notes [Member] \| Two Point Seven Seven Percent Notes Due Two Zero Five Three
Debt Instrument [Line Items]
Interest rate, stated percentage	2.77%	2.77%
Effective interest rate	5.20%	5.20%
Notes [Member] \| 1.65% notes due 2028 (1.65% 2028 Notes) [Member}
Debt Instrument [Line Items]
Interest rate, stated percentage	1.65%	1.65%
Face amount	$ 1,250	$ 1,250
Percentage of Principal Amount of Notes that may be Paid Upon Occurrence of Change in Control Triggering Event	101.00%
Notes [Member] \| 2.00% notes due 2032 (2.00% 2032 Notes) [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	2.00%	2.00%
Face amount	$ 1,250	$ 1,250
Percentage of Principal Amount of Notes that may be Paid Upon Occurrence of Change in Control Triggering Event	101.00%
Notes [Member] \| 2.80% notes due 2041 (2.80% 2041 Notes) [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	2.80%	2.80%
Face amount	$ 1,150	$ 1,150
Percentage of Principal Amount of Notes that may be Paid Upon Occurrence of Change in Control Triggering Event	101.00%
Notes [Member] \| 3.00% notes due 2052 (3.00% 2052 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	3.00%	3.00%
Face amount	$ 1,350	$ 1,350
Percentage of Principal Amount of Notes that may be Paid Upon Occurrence of Change in Control Triggering Event	101.00%
Minimum [Member] \| Debt Securities Payable [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Period without Payment of Make Whole Amount		2 months
Maximum [Member] \| Debt Securities Payable [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Period without Payment of Make Whole Amount		6 months

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