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Derivatives and Hedging Activity - Summary of Amounts of Derivative Gains (Losses) Recognized In Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Loss | [1] | $ (2.7) | $ 5.8
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | (0.9) | (0.5)
Amount of Gain Recognized in Earnings Related to Amount Excluded from Effectiveness Testing |  | 0.5 | 1.0
Interest Rate Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | $ (0.3) | $ (0.3)
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Interest Expense | Interest Expense
Foreign Exchange Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | $ 0.2 | $ 0.6
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Revenue from Contract with Customer, Excluding Assessed Tax | Revenue from Contract with Customer, Excluding Assessed Tax
Interest expense [Member] | Interest Rate Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Loss | [1] | $ 0.7 | $ (10.1)
Commission revenue [Member] | Foreign Exchange Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Loss | [1] | (3.4) | 15.9
Compensation expense [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | (0.5) | (0.5)
Amount of Gain Recognized in Earnings Related to Amount Excluded from Effectiveness Testing |  | $ 0.3 | $ 0.6
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Labor and Related Expense | Labor and Related Expense
Operating expense [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | $ (0.3) | $ (0.3)
Amount of Gain Recognized in Earnings Related to Amount Excluded from Effectiveness Testing |  | $ 0.2 | $ 0.4
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Operating Expenses | Operating Expenses
[1] | For the three-month period ended March 31, 2024, the amount excluded from the assessment of hedge effectiveness for our foreign exchange contracts recognized in accumulated other comprehensive loss was a gain of $0.3 million. For the three-month period ended March 31, 2023, the amount excluded from the assessment of hedge effectiveness for our foreign exchange contracts recognized in accumulated other comprehensive loss was a gain of $0.5 million.

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