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Income Taxes (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Income Taxes [Line Items] |  |  |
Net operating loss carryforwards, deferred tax assets | $ 82.1 | $ 70.5 |
Tax cuts and jobs act, income tax expense (benefit) |  | (16.4) |
Unrecognized tax benefits, interest and penalties, income tax expense | 1.4 | 0.5 | $ 0.7
Unrecognized tax benefits, accrued interest and penalties | 2.6 | 1.3 |
Unrecognized tax benefits | 18.4 |  |
State [Member] |  |  |
Income Taxes [Line Items] |  |  |
Net operating loss carryforwards, deferred tax assets | 15.7 | 11.5 |
Foreign [Member] |  |  |
Income Taxes [Line Items] |  |  |
Net operating loss carryforwards, deferred tax assets | 66.0 | 57.4 |
Federal [Member] |  |  |
Income Taxes [Line Items] |  |  |
Net operating loss carryforwards, deferred tax assets | $ 0.1 | $ 0.1 |

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- Definition Amount of income tax expense (benefit) from effect of Tax Cuts and Jobs Act. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 + Details
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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