Discontinued Operations - Loss, Assets and Liabilities of Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations, net of income taxes	$ 24.3	$ (2.3)	$ 20.0	$ (6.8)
Discontinued Operations, Held-for-sale or Disposed of by Sale
Liabilities:
Accounts payable and accrued expenses	43.8		43.8		$ 62.3
Other noncurrent liabilities	66.0		66.0		91.4
Total liabilities classified as discontinued operations	$ 109.8		$ 109.8		$ 153.7

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

- Definition

Amount classified as liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

+ References + Details