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Restructuring - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Estimate of cumulative pre tax costs that will result in cash outlays			55.00%
Estimate of cumulative pre tax costs that will be noncash			45.00%
Total pretax restructuring costs	$ 159	$ 235	$ 346	$ 339
Minimum
Restructuring Cost and Reserve [Line Items]
Expected restructuring and related cost	800		800
Maximum
Restructuring Cost and Reserve [Line Items]
Expected restructuring and related cost	$ 1,200		$ 1,200
Forecast
Restructuring Cost and Reserve [Line Items]
Expected restructuring and related cost					$ 500

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- Definition

Estimate of cumulative pre tax costs that will be noncash.

+ References

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- Definition

Estimate of cumulative pre tax costs that will result in cash outlays (primarily from employee separation expense).

+ References

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- Definition

Amount expected to be recognized in earnings for the specified restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b)(1))
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
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-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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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.

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