Amount after tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until disposal.

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Amount of cash inflow from the sale of investments classified as other.

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Discontinued Operations - Narrative (Details) - USD ($) $ in Millions		3 Months Ended
	Jun. 02, 2021	Mar. 31, 2022	Mar. 31, 2021	Jul. 22, 2021
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from discontinued operations, net of tax		$ 0.0	$ 21.9
Interests In Landmark
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Redemption of co-investments	$ 31.5
Discontinued Operations, Disposed of by Sale \| Interests In Landmark
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration	690.0
Discontinued Operations, Disposed of by Sale \| Thompson Siegel & Walmsley, LLC
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration				$ 240.0
Discontinued Operations, Held-for-sale \| Landmark Partners, LLC , Carried Interest And Co-Investments
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration	$ 31.5
Income from discontinued operations, net of tax			$ 3.1