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Employee Benefits (Narrative Defined Contribution Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
United States [Member]
Defined Contribution Plan [Line Items]
Maximum employee contribution as a percentage of annual compensation	100.00%
Employer contributions to plans	$ 21	$ 20	$ 21
Foreign Plan [Member]
Defined Contribution Plan [Line Items]
Employer Contributions to Plan	4	4	5
Defined Contribution Retirement Plan [Member] | United States [Member]
Defined Contribution Plan [Line Items]
Employer Contributions to Plan	$ 34	$ 32	$ 31

X

- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	duration

X

- Definition

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.

+ Details

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X

- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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X

- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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X

- Details

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X

- Details

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X

- Details

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