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Income Taxes Income Taxes (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2017
Income Taxes [Abstract] |  |  |  |  |
U.S. federal statutory rate | 21.00% | 35.00% | 21.00% | 35.00% |
Income Tax Limitation |  |  |  |  | $ 1.0
Deferred Tax Assets, Valuation Allowance | $ 6.3 |  | $ 6.3 |  | $ 5.5

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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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