Business Segment and Geographic Information (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) Division Countries	Dec. 31, 2019 USD ($) Countries	Dec. 31, 2018 Countries
Segment Reporting Information [Line Items]
Number of business segments \| Division	2
Maximum Percentage Revenue from One Geographic Segment	10.00%	10.00%	10.00%
Maximum Percentage Property Plant and Equipment from One Geographic Segment	10.00%	10.00%
Number of Countries Exceed Revenue Threshold \| Countries	1	1	1
Number of Countries Exceed Property Plant and Equipment Threshold \| Countries	1	1
Long-term debt \| $	$ 9,132	$ 10,316
Senior notes due March 2030
Segment Reporting Information [Line Items]
Long-term debt \| $	$ 1,000	$ 0
Property, Plant and Equipment [Member] \| UNITED STATES
Segment Reporting Information [Line Items]
Concentration Risk, Percentage	49.00%	59.00%
Revenue Benchmark [Member] \| UNITED STATES
Segment Reporting Information [Line Items]
Concentration Risk, Percentage	38.00%	51.00%	58.00%

The maximum percentage of property plant and equipment from one geographic location at balance sheet date.

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- Definition

The maximum percentage of revenue from one geographic segment for the periods presented.

+ References

No definition available.

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- Definition

The number of business segments into which the company's operations are divided.

+ References

No definition available.

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- Definition

The number of countries that exceed the property, plant and equipment threshold of 10%.

+ References

No definition available.

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The number of countries that exceed the revenue threshold of 10%.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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