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Taxes on Income - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax [Line Items]
U.S. statutory rate applied to income before taxes (as percent)	21.00%	35.00%	35.00%
Impact of the TCJA (as percent)	3.30%	40.30%	0.00%
Charge for one-time transition tax related to Tax Cuts and Jobs Act of 2017	$ 0	$ 5,347,000,000	$ 0
Reversal of deferred tax previously recorded		2,000,000,000
Measurement-period adjustment	124,000,000
Transition tax liability	4,900,000,000	5,500,000,000
Remeasurement of deferred taxes related to Tax Cuts and Jobs Act of 2017 provisional benefit		779,000,000
Measurement period adjustments related to deferred income taxes	32,000,000
Deferred tax assets on NOL carryforwards relating to foreign jurisdictions	715,000,000
NOL carryforwards relating to U.S. jurisdictions	0
Income taxes paid	1,500,000,000	4,900,000,000	1,800,000,000
Tax benefits relating to stock option exercises	77,000,000	73,000,000	147,000,000
Unrecognized tax benefits	1,893,000,000	1,723,000,000	3,494,000,000	$ 3,448,000,000
Favorable net impact to income tax provision if unrecognized tax benefits were recognized	1,800,000,000
Reasonably possible amount that liability for unrecognized tax benefits could decline up to in next 12 months (up to)	750,000,000
Interest and penalties associated with uncertain tax positions, expense (benefit)	51,000,000	183,000,000	134,000,000
Liabilities for accrued interest and penalties	372,000,000	341,000,000
Unrecognized tax benefits from adjustments related to examination	91,000,000	1,388,000,000	$ 92,000,000
Foreign Jurisdiction
Income Tax [Line Items]
Valuation allowance on foreign NOL carryforwards	1,300,000,000
Federal | Internal Revenue Service (IRS)
Income Tax [Line Items]
Income taxes paid		2,800,000,000
Unrecognized tax benefits from adjustments related to examination		$ 234,000,000
Income Taxes Payable
Income Tax [Line Items]
Transition tax liability, current	275,000,000
Other Noncurrent Liabilities
Income Tax [Line Items]
Transition tax liability, noncurrent	$ 4,600,000,000

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