v3.26.1
Changes in and Reclassifications out of Accumulated Other Comprehensive Loss (Detail) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning balance [1]     $ 2,150.4  
Interest and other borrowing costs $ 109.9 $ 123.8 220.3 $ 242.3
Income tax effect (11.8) (11.7) (23.2) (23.8)
Ending balance 2,230.3 2,081.7 2,230.3 2,081.7
Accumulated Gain (Loss) Net Cash Flow Hedge Parent        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning balance 4.5 5.0 3.7 7.9
Amounts recorded in AOCL related to Unrealized gain (loss) on derivative contracts, before tax 3.8 (1.3) 5.7 (3.8)
Amounts recorded in AOCL related to Unrealized gain (loss) on derivative contracts, income tax effect (0.9) 0.4 (1.4) 0.8
Net other comprehensive income (loss) 2.0 (0.2) 2.8 (3.1)
Ending balance 6.5 4.8 6.5 4.8
Accumulated Gain (Loss) Net Cash Flow Hedge Parent | Amounts reclassified out of AOCI        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Interest and other borrowing costs (1.2) 1.0 (2.0) (0.3)
Income tax effect $ 0.3 $ (0.3) $ 0.5 $ 0.2
[1] The December 31, 2025 balance sheet has been derived from audited financial statements.