PA Consulting Business Combination - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
Mar. 02, 2021	Jul. 02, 2021
Business Acquisition [Line Items]
Pre-tax transaction costs		$ 36.4
Preference share effect on basic earnings per share (in dollars per share)		$ 0.44
PA Consulting Employees
Business Acquisition [Line Items]
Ownership interest of employees	35.00%
Preferred stock cumulative dividend rate	12.00%
Redeemable noncontrolling interest exercise period	5 years
PA Consulting Group Limited
Business Acquisition [Line Items]
Percentage of outstanding shares of common and preferred stock acquired	65.00%
Consideration transferred	$ 1,700.0
Consideration received from acquiree	267.0
Fair value of redeemable noncontrolling interests at acquisition on March 2, 2021	$ 582.4
Cash in employee benefit trust		$ 12.6
PA Consulting Group Limited \| Customer Relationships, Contracts And Backlog And Trade names
Business Acquisition [Line Items]
Useful life of acquired intangible assets	12 years
PA Consulting Group Limited \| Customer Relationships, Contracts And Backlog And Trade names \| Minimum
Business Acquisition [Line Items]
Useful life of acquired intangible assets	9 years
PA Consulting Group Limited \| Customer Relationships, Contracts And Backlog And Trade names \| Maximum
Business Acquisition [Line Items]
Useful life of acquired intangible assets	20 years

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