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Employee Benefits Summary of Stock-Based Compensation (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] |  |  |
Share-based Compensation Expense | $ (636) | $ (845) | $ (649)
Share-based Payment Arrangement, Expense, Adjusted Tax Benefit | 2 |  |
Share-based Payment Arrangement, Expense, Tax Benefit |  | (164) | (280)
Stock-based compensation expense, Net of Tax | 638 | 681 | 369
Cost of Goods Sold |  |  |
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] |  |  |
Share-based Compensation Expense | (48) | (61) | (24)
Research and Development Expense [Member] |  |  |
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] |  |  |
Share-based Compensation Expense | (289) | (379) | (232)
Selling, General and Administrative Expenses [Member] |  |  |
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] |  |  |
Share-based Compensation Expense | $ (299) | $ (405) | $ (393)

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- Definition Amount of tax benefit for recognition of expense of award under share-based payment arrangement adjusted for a cumulative income tax effect, following the U.S. Court of Appeals decision in Altera Corp v. Commissioner. + References No definition available. + Details
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