Discontinued Operations - Additional Information (Details) $ in Millions	May 31, 2024 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Gain (Loss) on Disposal, Statement of Income or Comprehensive Income [Extensible Enumeration]	Gain (Loss) on Disposition of Business
Net gain on disposition of discontinued operations	$ 228.3
Marsh and McLennan Agency LLC [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash received from the sale of a business	$ 336.9

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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