Fair Value Measurements, Derivative Assets & Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Cumulative Amount of Fair Value Hedging Adjustment - Increase (Decrease) Included in Carrying Amount of Liability		$ 25
Long-term Obligations [Member]
Derivatives, Fair Value [Line Items]
Hedged Liability, Fair Value Hedge		1,020
Cumulative Amount of Fair Value Hedging Adjustment - Increase (Decrease) Included in Carrying Amount of Liability		25
Interest Rate Swaps [Member] \| Derivatives Designated as Hedging Instrument [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets		25
Interest Rate Swaps [Member] \| Fair Value Hedging [Member]
Derivatives, Fair Value [Line Items]
Notional Amount Of Derivatives		1,000
Cross Currency Interest Rate Contract [Member] \| Derivatives Designated as Hedging Instrument [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 25
Cross Currency Interest Rate Contract [Member] \| Derivatives Designated as Hedging Instrument [Member] \| Other Long-term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities		46
Cross Currency Interest Rate Contract [Member] \| Net Investment Hedging [Member]
Derivatives, Fair Value [Line Items]
Notional Amount Of Derivatives	900	900
Currency Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Notional Amount Of Derivatives	2,149	5,206
Currency Exchange Contracts [Member] \| Derivatives Not Designated as Hedging Instrument [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	11	3
Currency Exchange Contracts [Member] \| Derivatives Not Designated as Hedging Instrument [Member] \| Other Accrued Expenses [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	1	86
Fair Value, Recurring [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	36	28
Derivative Liabilities	$ 1	$ 132

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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