v3.24.2
Customer Funds - Gross Unrealized Losses and Related Fair Value of Investment (Detail)
$ in Millions
Jun. 30, 2024
USD ($)
Debt Securities, Available-for-sale [Line Items]  
Less than 12 months, Unrealized Losses $ (4.2)
Less than 12 months, Fair Value 447.6
12 months or more, Unrealized Losses (64.0)
12 months or more, Fair Value 1,407.8
Total, Unrealized Losses (68.2)
Total, Fair Value 1,855.4
U.S. Government and Agencies Securities [Member]  
Debt Securities, Available-for-sale [Line Items]  
Less than 12 months, Unrealized Losses (2.5)
Less than 12 months, Fair Value 191.3
12 months or more, Unrealized Losses (32.7)
12 months or more, Fair Value 519.0
Total, Unrealized Losses (35.2)
Total, Fair Value 710.3
Canadian and Provincial Government Securities [Member]  
Debt Securities, Available-for-sale [Line Items]  
Less than 12 months, Unrealized Losses (0.5)
Less than 12 months, Fair Value 64.6
12 months or more, Unrealized Losses (9.6)
12 months or more, Fair Value 274.8
Total, Unrealized Losses (10.1)
Total, Fair Value 339.4
Corporate Debt Securities [Member]  
Debt Securities, Available-for-sale [Line Items]  
Less than 12 months, Unrealized Losses (0.6)
Less than 12 months, Fair Value 110.5
12 months or more, Unrealized Losses (16.3)
12 months or more, Fair Value 433.5
Total, Unrealized Losses (16.9)
Total, Fair Value 544.0
Asset-backed Securities [Member]  
Debt Securities, Available-for-sale [Line Items]  
Less than 12 months, Unrealized Losses (0.3)
Less than 12 months, Fair Value 54.8
12 months or more, Unrealized Losses (2.3)
12 months or more, Fair Value 103.3
Total, Unrealized Losses (2.6)
Total, Fair Value 158.1
Mortgage-backed Securities [Member]  
Debt Securities, Available-for-sale [Line Items]  
Less than 12 months, Unrealized Losses (0.3)
Less than 12 months, Fair Value 23.4
12 months or more, Unrealized Losses (0.8)
12 months or more, Fair Value 13.8
Total, Unrealized Losses (1.1)
Total, Fair Value 37.2
Other Securities [Member]  
Debt Securities, Available-for-sale [Line Items]  
Less than 12 months, Fair Value 3.0
12 months or more, Unrealized Losses (2.3)
12 months or more, Fair Value 63.4
Total, Unrealized Losses (2.3)
Total, Fair Value $ 66.4