Debt - Summary of Outstanding Debt (Details) $ / shares in Units, € in Millions	1 Months Ended						3 Months Ended				12 Months Ended
	Feb. 28, 2019 USD ($)	Dec. 31, 2018 EUR (€)	Dec. 31, 2018 USD ($) $ / shares	Nov. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Feb. 28, 2017 USD ($) $ / shares	Dec. 31, 2018 USD ($) $ / shares	Sep. 30, 2018 $ / shares	Jun. 30, 2018 $ / shares	Mar. 31, 2018 $ / shares	Dec. 31, 2018 USD ($) $ / shares	Dec. 31, 2017 USD ($) $ / shares	Dec. 31, 2016 USD ($) $ / shares	Dec. 31, 2018	Dec. 31, 2018 Rate
Short-term
Commercial paper and U.S. bank borrowings			$ 829,000,000				$ 829,000,000				$ 829,000,000	$ 202,000,000
Other bank borrowings (primarily international)			656,000,000				656,000,000				656,000,000	36,000,000
Total short-term debt			1,485,000,000				1,485,000,000				1,485,000,000	238,000,000
Long-term
Carrying value of long-term debt including current portion			13,811,000,000				13,811,000,000				13,811,000,000	8,762,000,000
Less: current portion of long-term debt			(1,523,000,000)				(1,523,000,000)				(1,523,000,000)	(979,000,000)
Total long-term debt			12,288,000,000				12,288,000,000				12,288,000,000	7,783,000,000
Total debt			15,296,000,000				$ 15,296,000,000				15,296,000,000	9,000,000,000
Repayments of long-term debt											3,124,000,000	583,000,000	$ 770,000,000
Interest charge											$ 26,000,000	$ 0	$ 16,000,000
Extinguishment of debt, gain (loss), net of tax			$ 20,000,000			$ 10,000,000
Diluted earnings per share from continuing operations (in dollars per share) | $ / shares			$ 0.06			$ 0.04	$ 6.22	$ 1.58	$ 1.65	$ 1.59	$ 12.79	$ 4.32	$ 5.21
1.20% Notes due 2018
Long-term
Carrying value of long-term debt including current portion			$ 0				$ 0				$ 0	$ 498,000,000
Repayments of long-term debt					$ 500,000,000
Interest rate					1.20%					1.20%		1.20%
1.25% Notes due 2018
Long-term
Carrying value of long-term debt including current portion			0				0				0	$ 475,000,000
Repayments of long-term debt				$ 475,000,000
Interest rate				1.25%								1.25%
1.90% Notes due 2019
Long-term
Carrying value of long-term debt including current portion			500,000,000				500,000,000				500,000,000	$ 500,000,000
Interest rate														1.90%
Variable rate notes due 2019
Long-term
Carrying value of long-term debt including current portion			150,000,000				150,000,000				150,000,000	0
1.75% Euro denominated notes due 2019
Long-term
Carrying value of long-term debt including current portion			578,000,000				578,000,000				578,000,000	0
Interest rate														1.75%
4.25% AUD denominated notes due 2019
Long-term
Carrying value of long-term debt including current portion			71,000,000				71,000,000				71,000,000	0
Interest rate														4.25%
4.50% Notes due 2019 (d)
Long-term
Carrying value of long-term debt including current portion			0				0				0	$ 599,000,000
Repayments of long-term debt			600,000,000
Interest rate												4.50%		4.50%	4.50%
Variable rate notes due 2019
Long-term
Carrying value of long-term debt including current portion			200,000,000				200,000,000				200,000,000	$ 0
1.50% Euro denominated notes due 2020
Long-term
Carrying value of long-term debt including current portion			0				0				0	$ 717,000,000
Repayments of long-term debt | €		€ 600
Interest rate												1.50%		1.50%
2.25% Notes due 2020
Long-term
Carrying value of long-term debt including current portion			299,000,000				299,000,000				299,000,000	$ 299,000,000
Interest rate														2.25%
1.75% Euro denominated notes due 2020
Long-term
Carrying value of long-term debt including current portion			1,185,000,000				1,185,000,000				1,185,000,000	0
Interest rate														1.75%
0.634% Euro denominated notes due 2020
Long-term
Carrying value of long-term debt including current portion			58,000,000				58,000,000				58,000,000	0
Interest rate														0.634%
4.05% Notes due 2021
Long-term
Carrying value of long-term debt including current portion			499,000,000				499,000,000				499,000,000	498,000,000
Interest rate														4.05%
3.875% Euro denominated notes due 2021
Long-term
Carrying value of long-term debt including current portion			755,000,000				755,000,000				755,000,000	0
Interest rate														3.875%
3.125% Euro denominated notes
Long-term
Repayments of long-term debt | €		€ 750
Interest rate														3.125%
3.00% Notes due 2021
Long-term
Carrying value of long-term debt including current portion			498,000,000				498,000,000				498,000,000	497,000,000
Interest rate														3.00%
0.250% Euro denominated notes due 2022
Long-term
Carrying value of long-term debt including current portion			1,156,000,000				1,156,000,000				1,156,000,000	0
Interest rate														0.25%
2.45% Notes due 2022
Long-term
Carrying value of long-term debt including current portion			598,000,000				598,000,000				598,000,000	598,000,000
Interest rate														2.45%
2.20% Notes due 2022
Long-term
Carrying value of long-term debt including current portion			498,000,000				498,000,000				498,000,000	498,000,000
Interest rate														2.20%
2.70% Notes due 2023
Long-term
Carrying value of long-term debt including current portion			498,000,000				498,000,000				498,000,000	498,000,000
Interest rate														2.70%
2.00% Euro denominated notes due 2023
Long-term
Carrying value of long-term debt including current portion			805,000,000				805,000,000				805,000,000	0
Interest rate														2.00%
5.875% GBP denominated notes due 2023
Long-term
Carrying value of long-term debt including current portion			454,000,000				454,000,000				454,000,000	0
Interest rate														5.875%
1.20% Euro denominated notes due 2024
Long-term
Carrying value of long-term debt including current portion			628,000,000				628,000,000				628,000,000	658,000,000
Interest rate														1.20%
1.875% Euro denominated notes due 2024
Long-term
Carrying value of long-term debt including current portion			373,000,000				373,000,000				373,000,000	0
Interest rate														1.875%
2.65% Notes due 2025
Long-term
Carrying value of long-term debt including current portion			398,000,000				398,000,000				398,000,000	397,000,000
Interest rate														2.65%
1.625% Euro denominated notes due 2025
Long-term
Carrying value of long-term debt including current portion			568,000,000				568,000,000				568,000,000	594,000,000
Interest rate														1.625%
3.20% Notes due 2026
Long-term
Carrying value of long-term debt including current portion			725,000,000				725,000,000				725,000,000	725,000,000
Interest rate														3.20%
3.434% Notes due 2026
Long-term
Carrying value of long-term debt including current portion			195,000,000				195,000,000				195,000,000	0
Interest rate														3.434%
1.652% Euro denominated notes due 2027
Long-term
Carrying value of long-term debt including current portion			96,000,000				96,000,000				96,000,000	0
Interest rate														1.652%
1.00% Euro denominated notes due 2028
Long-term
Carrying value of long-term debt including current portion			861,000,000				861,000,000				861,000,000	0
Interest rate														1.00%
1.90% Euro denominated notes due 2030
Long-term
Carrying value of long-term debt including current portion			121,000,000				121,000,000				121,000,000	0
Interest rate														1.90%
3.55% Notes due 2042
Long-term
Carrying value of long-term debt including current portion			662,000,000				662,000,000				662,000,000	662,000,000
Interest rate														3.55%
Other
Long-term
Carrying value of long-term debt including current portion			10,000,000				10,000,000				10,000,000	12,000,000
International bank borrowings
Long-term
Carrying value of long-term debt including current portion			291,000,000				291,000,000				291,000,000	33,000,000
Obligations under capital lease
Long-term
Carrying value of long-term debt including current portion			81,000,000				$ 81,000,000				81,000,000	4,000,000
4.50% Notes Due 2019 and 1.50% Notes Due 2020
Long-term
Interest charge											26,000,000
Extinguishment of debt, gain (loss), net of tax			$ 20,000,000
Diluted earnings per share from continuing operations (in dollars per share) | $ / shares			$ 0.06
Derivatives Designated as Hedging Instruments - Fair Value | Interest rate swaps | Derivatives Designated as Hedging Instruments:
Long-term
Change in Fair Value											(14,000,000)	0
Derivatives Designated as Hedging Instruments - Fair Value | Interest rate swaps | Derivatives Designated as Hedging Instruments: | 1.25% Notes due 2018
Long-term
Change in Fair Value											0	0
Derivatives Designated as Hedging Instruments - Fair Value | Interest rate swaps | Derivatives Designated as Hedging Instruments: | 1.75% Euro denominated notes due 2019
Long-term
Change in Fair Value											1,000,000	0
Derivatives Designated as Hedging Instruments - Fair Value | Interest rate swaps | Derivatives Designated as Hedging Instruments: | 1.75% Euro denominated notes due 2020
Long-term
Change in Fair Value											0	0
Derivatives Designated as Hedging Instruments - Fair Value | Interest rate swaps | Derivatives Designated as Hedging Instruments: | 3.875% Euro denominated notes due 2021
Long-term
Change in Fair Value											(1,000,000)	0
Derivatives Designated as Hedging Instruments - Fair Value | Interest rate swaps | Derivatives Designated as Hedging Instruments: | 0.250% Euro denominated notes due 2022
Long-term
Change in Fair Value											(2,000,000)	0
Derivatives Designated as Hedging Instruments - Fair Value | Interest rate swaps | Derivatives Designated as Hedging Instruments: | 2.00% Euro denominated notes due 2023
Long-term
Change in Fair Value											(2,000,000)	0
Derivatives Designated as Hedging Instruments - Fair Value | Interest rate swaps | Derivatives Designated as Hedging Instruments: | 5.875% GBP denominated notes due 2023
Long-term
Change in Fair Value											(1,000,000)	0
Derivatives Designated as Hedging Instruments - Fair Value | Interest rate swaps | Derivatives Designated as Hedging Instruments: | 1.875% Euro denominated notes due 2024
Long-term
Change in Fair Value											(1,000,000)	0
Derivatives Designated as Hedging Instruments - Fair Value | Interest rate swaps | Derivatives Designated as Hedging Instruments: | 1.00% Euro denominated notes due 2028
Long-term
Change in Fair Value											$ (8,000,000)	$ 0
Subsequent Event | 1.90% Notes due 2019
Long-term
Repayments of long-term debt	$ 500,000,000
Interest rate	1.90%