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Income Taxes (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Operating Loss Carryforwards [Line Items] |  |  |
Provisional tax benefit from remeasurement of deferred tax liabilities | $ 16.2 |  |
Transition tax for foreign earnings | $ 3.7 |  |
Statutory tax rate, percentage | 35.00% | 35.00% | 35.00%
Deferred tax assets, net of operating losses | $ 22.5 |  |
Deferred tax assets, net of operating losses | 3.5 |  |
Undistributed earnings of foreign subsidiaries | 27.2 |  |
Cash held in foreign operations | 24.4 |  |
Unrecognized tax benefits that would affect the effective tax rate | $ 0.3 | $ 0.6 |
Minimum |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Statute of limitations expiration period, in years | 4 years |  |
Maximum |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Statute of limitations expiration period, in years | 10 years |  |
RBI |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Unrecognized tax benefits that would affect the effective tax rate | $ 3.2 | $ 2.8 |

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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=96869850&loc=d3e28680-109314 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32632-109319 + Details
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