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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 | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Loss | [1] | $ 152.5 | $ 22.3
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | 3.2 | (5.8)
Amount of Gain (Loss) Recognized in Earnings Related to Amount Excluded from Effectiveness Testing |  | 3.2 | 1.7
Interest Rate Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | $ (1.2) | $ (1.1)
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Interest | Interest
Foreign Exchange Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | $ 6.3 | $ (3.3)
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Total revenues | Total revenues
Interest expense [Member] | Interest Rate Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Loss | [1] | $ 179.3 | $ 35.8
Commission revenue [Member] | Foreign Exchange Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Loss | [1] | (26.8) | (13.5)
Amount of Gain (Loss) Recognized in Earnings Related to Amount Excluded from Effectiveness Testing |  | (0.1) |
Compensation expense [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | $ (1.1) | $ (0.8)
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Compensation | Compensation
Amount of Gain (Loss) Recognized in Earnings Related to Amount Excluded from Effectiveness Testing |  | $ 1.9 | $ 1.0
Operating expense [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | $ (0.8) | $ (0.6)
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Operating | Operating
Amount of Gain (Loss) Recognized in Earnings Related to Amount Excluded from Effectiveness Testing |  | $ 1.4 | $ 0.7
[1] | During 2022, the amount excluded from the assessment of hedge effectiveness for our foreign exchange contracts recognized in accumulated other comprehensive loss was a gain of $0.9 million.

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