The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Goodwill and Other Intangible Assets (Summary of Intangible Assets) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Goodwill and Other Intangible Assets
Accumulated Amortization	$ (699)		$ (699)		$ (603)
Intangible Assets Gross, Carrying Amount	1,879		1,879		1,835
Intangible Assets, Net Intangibles	1,180		1,180		1,232
Amortization	35	$ 34	104	$ 108
Customer and distributor relationships
Goodwill and Other Intangible Assets
Carrying Amount	939		939		951
Accumulated Amortization	(334)		(334)		(286)
Net Intangibles	605		605		665
Proprietary technology and patents
Goodwill and Other Intangible Assets
Carrying Amount	203		203		198
Accumulated Amortization	(105)		(105)		(93)
Net Intangibles	98		98		105
Trademarks
Goodwill and Other Intangible Assets
Carrying Amount	147		147		148
Accumulated Amortization	(49)		(49)		(41)
Net Intangibles	98		98		107
Software
Goodwill and Other Intangible Assets
Carrying Amount	405		405		355
Accumulated Amortization	(195)		(195)		(164)
Net Intangibles	210		210		191
Other
Goodwill and Other Intangible Assets
Carrying Amount	20		20		24
Accumulated Amortization	(16)		(16)		(19)
Net Intangibles	4		4		5
Indefinite-lived intangibles
Goodwill and Other Intangible Assets
Accumulated Amortization	0		0		0
Indefinite-lived intangibles	$ 165		$ 165		$ 159