Revenue Contract Balances (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Accounts receivable, net of allowance of $35.5 and $37.0, respectively	$ 4,644.1	$ 5,649.7
Accounts receivable, billable to clients	2,163.4	2,088.4
Contract assets	48.7	50.1
Contract liabilities (deferred revenue)	598.4	$ 509.0
Revenue, Remaining Performance Obligation, Amount	$ 579.3

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

+ References

No definition available.

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