Discontinued Operations and Disposal Groups - Results of Operations (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Results of Operations, Discontinued Operations
Income from discontinued operations, net of income taxes	$ (0.8)	$ 5.9
Oxford Business \| Discontinued Operations
Results of Operations, Discontinued Operations
Revenues		118.6
Costs of services		81.4
Gross profit		37.2
Selling, general and administrative expenses		29.6
Amortization of intangible assets		0.2
Income before income taxes		7.4
Provision for income taxes		1.5
Income from discontinued operations, net of income taxes		$ 5.9

Net Income from Discontinued Operations

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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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Amount of costs of goods sold attributable to disposal group, including, but not limited to, discontinued operation.

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