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Income Taxes (Details) - USD ($) $ in Thousands |  | 3 Months Ended
--- | --- | ---
Dec. 22, 2017 | Dec. 31, 2017 | Dec. 31, 2016
Income Taxes |  |  |
Number of years rate reduction will be phased in | 2 years |  |
Blended federal statutory income tax rate (as a percent) | 24.50% |  |
Enacted federal statutory income tax rate for next fiscal years (as a percent) | 21.00% | 21.00% |
Income tax benefit |  | $ 500,641 | $ 18,288
Effective income tax rate (as a percent) |  | 50064100.00% | 34.60%
Income tax benefit relating to re-measurement of net deferred tax liability from new tax Act |  | $ 500,400 |
Foreign transition tax liability |  | 0 |
Income tax benefit normally reported as a component of AOCI due to new tax act |  | $ 300 |

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- Definition Percentage of enacted domestic federal statutory tax rate applicable to pretax income (loss) for next fiscal year. + References No definition available. + Details
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- Definition Represents the foreign transition income tax liability relating to the new tax legislation. + References No definition available. + Details
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- Definition Income tax benefit from continuing operations for items which are normally reported as a component of Accumulated Other Comprehensive Income (AOCI) due to the new tax legislation. + References No definition available. + Details
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- Definition The income tax benefit relating to the re-measurement of the entity's net deferred tax liability as a result of the new corporate income tax rate from the new tax legislation. + References No definition available. + Details
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(2)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: 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 + Details
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