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Number of plaintiffs that have filed claims pertaining to a loss contingency.

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The amount of cash paid for the settlement of litigation or for other legal issues during the period.

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Amount of unrecognized tax benefits.

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Contingencies (Details) $ in Millions	1 Months Ended
Contingencies (Details) $ in Millions	Aug. 31, 2021 plaintiff	May 31, 2021 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Loss Contingencies [Line Items]
Accrual of loss contingency				$ 15.0
Estimate of possible loss				45.0
Unrecognized tax benefits				252.0	$ 308.0	$ 149.0	$ 108.0
Invoicing Matter
Loss Contingencies [Line Items]
Payments for settlements			$ 48.8
Invoicing Matter \| United States Attorney For The District of Massachusetts
Loss Contingencies [Line Items]
Payments for settlements		$ 115.0
Invoicing Matter \| U.S. Securities And Exchange Commission
Loss Contingencies [Line Items]
Amount awarded to other party			40.0
Invoicing Matter \| Massachusetts Attorney General
Loss Contingencies [Line Items]
Amount awarded to other party			$ 5.5
Gomes v State Street Corp.
Loss Contingencies [Line Items]
Loss contingency, number of plaintiffs \| plaintiff	8
Edmar Financial Company, LLC v. Currenex, Inc.
Loss Contingencies [Line Items]
Loss contingency, number of plaintiffs \| plaintiff	2
Legal Reserve \| Invoicing Matter
Loss Contingencies [Line Items]
Estimate of possible loss				$ 355.0