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Income Taxes (ASC 740-10) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
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 |  |  |
Balance at beginning | $ 1.1 | $ 0.3 | $ 0.0
Changes in prior year tax positions | 1.3 | 0.8 | 0.1
Tax positions taken during the current year |  |  | 0.2
Balance at year end | 2.4 | 1.1 | 0.3
Permanent Differences |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns |  |  |
Balance at beginning | 1.1 | 0.3 | 0.0
Changes in prior year tax positions | 1.3 | 0.8 | 0.1
Tax positions taken during the current year |  |  | 0.2
Balance at year end | 2.4 | 1.1 | 0.3
Temporary Differences |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns |  |  |
Balance at beginning | 0.0 | 0.0 | 0.0
Changes in prior year tax positions |  | 0.0 | 0.0
Tax positions taken during the current year |  |  | 0.0
Balance at year end | 0.0 | 0.0 | 0.0
Interest and Penalties Net of Tax Benefit |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns |  |  |
Balance at beginning | 0.0 | 0.0 | 0.0
Changes in prior year tax positions |  | 0.0 | 0.0
Tax positions taken during the current year |  |  | 0.0
Balance at year end | $ 0.0 | $ 0.0 | $ 0.0

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