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Restructuring Actions and Exit Activities - Roll Forward (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	9 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
2019 Restructuring Actions
Restructuring Reserve Roll Forward
Expenses incurred	$ 148
Non-cash changes	(76)
Cash payments	(6)
Restructuring actions balances, Ending Balance	66	$ 66
2018 Restructuring Actions
Restructuring Reserve Roll Forward
Restructuring actions balances, Beginning Balance		84
Expenses incurred			$ 137
Non-cash changes			(12)
Cash payments		(57)	(24)
Adjustments		(2)	(17)
Restructuring actions balances, Ending Balance	25	25	84
Employee-Related \| 2019 Restructuring Actions
Restructuring Reserve Roll Forward
Expenses incurred	108
Non-cash changes	(36)
Cash payments	(6)
Restructuring actions balances, Ending Balance	66	66
Employee-Related \| 2018 Restructuring Actions
Restructuring Reserve Roll Forward
Restructuring actions balances, Beginning Balance		84
Expenses incurred			125
Cash payments		(57)	(24)
Adjustments		(2)	(17)
Restructuring actions balances, Ending Balance	25	$ 25	84
Asset-Related \| 2019 Restructuring Actions
Restructuring Reserve Roll Forward
Expenses incurred	40
Non-cash changes	$ (40)
Asset-Related \| 2018 Restructuring Actions
Restructuring Reserve Roll Forward
Expenses incurred			12
Non-cash changes			$ (12)