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Income Taxes (Uncertain Tax Positions) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Income Tax Contingency [Line Items] |  |
Percentage of likelihood for realization of benefit upon ultimate settlement |  | 50.00%
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns |  |
Beginning balance | $ 0.0 |
Changes in prior year tax positions | 0.1 |
Tax positions taken during the current year | 0.2 |
Ending balance | 0.3 | $ 0.0
Permanent Differences |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns |  |
Beginning balance | 0.0 |
Changes in prior year tax positions | 0.1 |
Tax positions taken during the current year | 0.2 |
Ending balance | 0.3 | 0.0
Temporary Differences |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns |  |
Beginning balance | 0.0 |
Changes in prior year tax positions | 0.0 |
Tax positions taken during the current year | 0.0 |
Ending balance | 0.0 | 0.0
Interest and Penalties Net of Tax Benefit |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns |  |
Beginning balance | 0.0 |
Changes in prior year tax positions | 0.0 |
Tax positions taken during the current year | 0.0 |
Ending balance | $ 0.0 | $ 0.0

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- Definition Amount of unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details
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