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Income Taxes (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Sep. 30, 2018 | Dec. 31, 2017
Income Tax Disclosure [Abstract] |  |
Net operating loss carryforwards | $ 153,500,000 |
Valuation allowance | 0 | $ 0
Information regarding income tax examinations [Abstract] |  |
Decrease in unrecognized tax benefits upon settlement of IRS dispute | 144,900,000 |
Total amount of unrecognized tax benefits | $ 0 |

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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + 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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