Financing arrangements (Debt Issuances) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Aggregate principal amount of notes issued	$ 4,500,000,000.0	$ 6,700,000,000	$ 3,500,000,000.0
Short-term loan		$ 605,000,000	0
1.85% notes due 2021 (1.85% 2021 Notes) [Member]
Debt Instrument [Line Items]
Stated contractual interest rate on note		1.85%
1.25% notes due 2022 (1.25% 2022 euro Notes) [Member]
Debt Instrument [Line Items]
Stated contractual interest rate on note		1.25%
0.41% 2023 Swiss franc Bonds [Member]
Debt Instrument [Line Items]
Stated contractual interest rate on note		0.41%
2.25% notes due 2023 (2.25% 2023 Notes) [Member]
Debt Instrument [Line Items]
Stated contractual interest rate on note		2.25%
2.00% 2026 euro Notes [Member]
Debt Instrument [Line Items]
Stated contractual interest rate on note		2.00%
2.60% notes due 2026 (2.60% 2026 notes) [Member]
Debt Instrument [Line Items]
Stated contractual interest rate on note		2.60%
4.40% notes due 2045 (4.40% 2045 Notes) [Member]
Debt Instrument [Line Items]
Aggregate principal amount of notes issued		$ 1,000,000,000	$ 1,250,000,000.00
Stated contractual interest rate on note		4.40%	4.40%
2.125% notes due 2020 (2.125% 2020 Notes) [Member]
Debt Instrument [Line Items]
Stated contractual interest rate on note		2.125%	2.125%
2.70% notes due 2022 (2.70% 2022 Notes) [Member]
Debt Instrument [Line Items]
Stated contractual interest rate on note		2.70%	2.70%
3.125% notes due 2025 (3.125% 2025 Notes) [Member]
Debt Instrument [Line Items]
Stated contractual interest rate on note		3.125%	3.125%
1.25% notes due 2017 (1.25% 2017 Notes) [Member]
Debt Instrument [Line Items]
Stated contractual interest rate on note	1.25%	1.25%
2.20% notes due 2019 (2.20% 2019 Notes) [Member]
Debt Instrument [Line Items]
Stated contractual interest rate on note	2.20%	2.20%
3.625% notes due 2024 (3.625% 2024 Notes) [Member]
Debt Instrument [Line Items]
Stated contractual interest rate on note	3.625%	3.625%
Floating rate notes due 2017 [Member] | Three-Month LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.38%
Floating rate notes due 2019 [Member] | Three-Month LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.60%
Senior Notes [Member] | 4.40% notes due 2045 (4.40% 2045 Notes) [Member]
Debt Instrument [Line Items]
Debt instrument, unamortized premium		$ 79,000,000