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Income Taxes - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Income Taxes [Line Items] |  |  |
Federal statutory income tax rate | 21.00% |  |
Income tax benefit for the one-time transition tax | $ 4 |  |
Unrecognized tax benefits | 39 | $ 21 | $ 74
Unrecognized tax benefits that would impact effective tax rate if recognized | 39 |  |
2030 |  |  |
Income Taxes [Line Items] |  |  |
NOL carry forwards | 600 |  |
Thereafter |  |  |
Income Taxes [Line Items] |  |  |
NOL carry forwards | 1,000 |  |
Federal |  |  |
Income Taxes [Line Items] |  |  |
NOL carry forwards | 1,600 |  |
State |  |  |
Income Taxes [Line Items] |  |  |
NOL carry forwards | 83 |  |
NOL carry forwards, valuation allowance | $ 48 |  |

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- Definition Effective Income Tax Rate Reconciliation, Tax Cuts And Jobs Act Of 2017, Transition Tax On Accumulated Foreign Earnings, Amount + References No definition available. + Details
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- Definition Income Taxes [Line Items] + 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://www.xbrl.org/2003/role/presentationRef -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/2003/role/presentationRef -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=34349781&loc=d3e330036-122817 Reference 3: http://www.xbrl.org/2003/role/presentationRef -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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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319 + Details
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