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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, 2021 | Dec. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Loss | [1] | $ 22.3 | $ (97.1)
Amount of Loss Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | (5.8) | (6.3)
Amount of Gain (Loss) Recognized in Earnings Related to Amount Excluded from Effectiveness Testing |  | 1.7 | 2.3
Interest expense [Member] | Interest Rate Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Loss | [1] | 35.8 | (92.5)
Amount of Loss Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | (1.1) | (1.1)
Commission revenue [Member] | Foreign Exchange Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Loss | [1] | (13.5) | (4.6)
Amount of Loss Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | (3.3) | (2.4)
Amount of Gain (Loss) Recognized in Earnings Related to Amount Excluded from Effectiveness Testing |  |  | (0.4)
Compensation expense [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Loss Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | (0.8) | (1.6)
Amount of Gain (Loss) Recognized in Earnings Related to Amount Excluded from Effectiveness Testing |  | 1.0 | 1.6
Operating expense [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Loss Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | (0.6) | (1.2)
Amount of Gain (Loss) Recognized in Earnings Related to Amount Excluded from Effectiveness Testing |  | $ 0.7 | $ 1.1
[1] | During 2021, the amount excluded from the assessment of hedge effectiveness for our foreign exchange contracts recognized in accumulated other comprehensive loss was a loss of $1.2 million.

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