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Taxes on Income - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income Tax [Line Items] |  |  |  |
Transition tax for accumulated foreign earnings, liability | $ 3,000 |  |  |
Deferred tax assets on NOL carryforwards relating to foreign jurisdictions | 464 |  |  |
Deferred tax assets relating to various U.S. tax credit carryforwards and NOL carryforwards | 330 |  |  |
Income taxes paid | 2,700 | $ 4,500 | $ 1,500 |
Tax benefits relating to stock option exercises | 55 | 65 | 77 |
Unrecognized tax benefits | 1,537 | 1,225 | 1,893 | $ 1,723
Favorable net impact to income tax provision if unrecognized tax benefits were recognized | 1,500 |  |  |
Reasonably possible amount that liability for unrecognized tax benefits could decline up to in next 12 months (up to) | 160 |  |  |
Interest and penalties associated with uncertain tax positions, expense (benefit) | 27 | (101) | 51 |
Liabilities for accrued interest and penalties | 268 | 243 |  |
Unrecognized tax benefits from adjustments related to examination | 70 | 356 | $ 91 |
Foreign Jurisdiction |  |  |  |
Income Tax [Line Items] |  |  |  |
Valuation allowance on foreign NOL carryforwards | 433 |  |  |
Federal | Internal Revenue Service (IRS) |  |  |  |
Income Tax [Line Items] |  |  |  |
Income taxes paid |  | 107 |  |
Unrecognized tax benefits from adjustments related to examination |  | $ 364 |  |
Income Taxes Payable |  |  |  |
Income Tax [Line Items] |  |  |  |
Transition tax liability, current | 390 |  |  |
Other Noncurrent Liabilities |  |  |  |
Income Tax [Line Items] |  |  |  |
Transition tax liability, noncurrent | $ 2,600 |  |  |

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- Definition Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d)(3) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign operating loss carryforwards. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32632-109319 + Details
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