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Income Taxes (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Mar. 31, 2019
Income Taxes [Line Items] |  |  |  |
Federal corporate income tax rate |  | 21.00% | 35.00% |
Reduction of net deferred tax liabilities | $ 31 | $ 120 | $ 12,682 |
Deferred tax liability attributable to temporary differences in other comprehensive income | 118 |  |  |
Change in net deferred tax liability related to acquisitions | 1,000 |  |  |
Net deferred tax liability, franchise rights | 15,400 |  |  |
Liability for uncertain tax positions | 1,013 | 1,012 | $ 809 |
Unrecognized tax benefits that would impact effective tax rate | 1,100 |  |  |
Unrecognized tax benefits, interest on income taxes accrued | 186 | $ 203 |  |
Federal Tax Authority [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Operating loss carryforwards | 274 |  |  |
Foreign Tax Authority [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Operating loss carryforwards | $ 5,600 |  |  |
Sky Limited [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Deferred tax assets related to net operating losses |  |  |  | $ 1,200

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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax reform legislation. + References No definition available. + Details
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- Definition [Line Items] for Income Taxes [Table] + References No definition available. + Details
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
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