Discontinued Operations and Special (Gains) Charges - Narrative (Details) - Discontinued Operations - Disposed of by Sale - NATG $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Restitution receipts	$ 15.0
Ongoing restitution proceedings	3.0
Vendor settlements	0.1
Benefit from settlements of payable accounts	0.5
Tax effect of discontinued operation	2.9
Maximum
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional charges (less than)	$ 0.5

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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