Risk Management Derivative in Net Investment (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Foreign currency contracts	$ 111	$ 145	$ (104)
Net Investment Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Loss on impairments and divestitures, net	26	0	0
Other, net	0	0	0
Net Investment Hedging [Member] \| Other Comprehensive Income (Loss) \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Foreign currency contracts	91	0	0
Net Investment Hedging [Member] \| Other Comprehensive Income (Loss) \| Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member]
Derivative [Line Items]
Foreign currency contracts	91	0	0
(Gain) loss on divestitures and impairments, net \| Net Investment Hedging [Member] \| Designated as Hedging Instrument [Member] \| Currency Swap [Member]
Derivative [Line Items]
Loss on impairments and divestitures, net	26
(Gain) loss on divestitures and impairments, net \| Net Investment Hedging [Member] \| Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member]
Derivative [Line Items]
Loss on impairments and divestitures, net	26	0	0
Other Nonoperating Income (Expense) [Member] \| Net Investment Hedging [Member] \| Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member]
Derivative [Line Items]
Other, net	$ 0	$ 0	$ 0

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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