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Amount of unrecognized tax benefits.

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Contingencies (Details) - USD ($) $ in Millions	1 Months Ended
Contingencies (Details) - USD ($) $ in Millions	May 31, 2021	Jun. 30, 2019	Jun. 30, 2021	Dec. 31, 2020
Loss Contingencies [Line Items]
Accrual of loss contingency			$ 21.0
Estimate of possible loss			40.0
Unrecognized tax benefits			295.0	$ 308.0
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]
Amount awarded to other party	$ 115.0
Invoicing Matter \| Massachusetts Attorney General
Loss Contingencies [Line Items]
Amount awarded to other party		5.5
Invoicing Matter \| U.S. Securities and Exchange Commission
Loss Contingencies [Line Items]
Amount awarded to other party		$ 40.0
Legal Reserve \| Invoicing Matter
Loss Contingencies [Line Items]
Estimate of possible loss			$ 366.0