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Income Taxes (Federal Statutory) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income Taxes [Line Items] |  |  |
Federal tax at statutory rate | $ (3,569) | $ (3,201) | $ (5,374)
State income taxes, net of federal benefit | (306) | (212) | (299)
Foreign income taxed at different rates | (126) | (147) | (70)
Nontaxable income attributable to noncontrolling interests | 51 | 20 | 45
Other adjustments | 40 | 138 | 229
Excess tax benefits recognized on share-based compensation | 196 | 75 | 297
Tax legislation | 31 | 120 | 12,682
Income tax (expense) benefit | (3,673) | (3,380) | 7,569
Adjustments to uncertain and effectively settled tax positions, net [Member] |  |  |
Income Taxes [Line Items] |  |  |
Other adjustments | (3) | (144) | 62
Accrued interest on uncertain and effectively settled tax positions, net [Member] |  |  |
Income Taxes [Line Items] |  |  |
Other adjustments | $ 13 | $ (29) | $ (3)

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- Definition Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 740 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=117330312&loc=d3e23163-113944 + Details
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