Tax Cuts and Jobs Act, Incomplete Accounting, Change in Tax Rate, Provisional Income Tax Expense (Benefit)

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Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Income Tax Expense (Benefit)

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Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Liability

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Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiaries and other recognized entities not within the country of domicile of the entity.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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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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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

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Taxes on Income - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Income Tax Examination [Line Items]
Effective income tax rate (as percent)	17.80%	20.00%	28.40%	21.00%
Research and development	$ 2,274	$ 1,782	$ 5,470	$ 3,612
Tax benefit related to settlement of state income tax issue		$ 88		$ 88
Transition tax liability					$ 5,300
Net transition tax payment					5,100
Provisional deferred tax benefit					779
2017 Tax Cuts and Jobs Act (TCJA)
Income Tax Examination [Line Items]
Deferred taxes					$ 2,000
Eisai
Income Tax Examination [Line Items]
Research and development			$ 1,400