Net discrete tax provision (benefit) due to dicrete events, such as changes in tax rate or tax law.

No definition available.

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- Definition

Intermittent net discrete tax provision (benefit) due to change in tax laws.

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No definition available.

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- Definition

Intermittent net discrete tax provision (benefit) due to dicrete events, such as changes in tax rate or tax law.

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No definition available.

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- Definition

Intermittent net discrete tax provision (benefit) due to other changes.

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No definition available.

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- Definition

Net discrete tax provision (benefit) resulting from recording all of the tax effects related to employee share-based award payments at settlement (or expiration) through the income statement.

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- Definition

Intermittent net discrete tax provision (benefit) associated with the remeasurement of reserves and related interest relating to the status of multi-year tax examinations.

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No definition available.

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- 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.

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Segment, Geographic and Revenue Information (Net Discrete Tax Provision (Benefit) by Segment) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information
Intermittent: Tax Act enactment				$ 1,201
Intermittent: Remeasurement of reserves and related interest	$ (111)	$ (168)		(168)
Intermittent: Other				(65)
Total intermittent net discrete tax provision (benefit)			$ (203)	968	$ (68)
Recurring: Employee share-based awards			(165)	(155)
Total			(368)	813
IS
Segment Reporting Information
Intermittent: Tax Act enactment				705
Intermittent: Remeasurement of reserves and related interest				(168)
Intermittent: Other				(66)
Total intermittent net discrete tax provision (benefit)			(182)	471
Recurring: Employee share-based awards			(104)	(93)
Total			(286)	378
WM
Segment Reporting Information
Intermittent: Tax Act enactment				402
Intermittent: Remeasurement of reserves and related interest				0
Intermittent: Other				9
Total intermittent net discrete tax provision (benefit)			0	411
Recurring: Employee share-based awards			(50)	(54)
Total			(50)	357
IM
Segment Reporting Information
Intermittent: Tax Act enactment				94
Intermittent: Remeasurement of reserves and related interest				0
Intermittent: Other				(8)
Total intermittent net discrete tax provision (benefit)			(21)	86
Recurring: Employee share-based awards			(11)	(8)
Total			$ (32)	$ 78