Basis of Presentation (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) segment	Mar. 31, 2020 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of reportable segments \| segment	1
Net income (loss) from discontinued operations	$ 9.7	$ (0.1)
Legal Fees \| Immediate Family Member of Management or Principal Owner
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Expenses from transaction with related party	3.0
Discontinued Operations - Disposed of by Sale \| NATG
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net income (loss) from discontinued operations	9.7	$ (0.1)
Restitution receipts	$ 15.0

Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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+ Details