Lease Accounting - Schedule of Aggregate Lease Costs by Lease Classification (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Lease Cost [Line Items]
Total operating lease costs		$ 86.1	$ 84.8	$ 166.8	$ 166.2
Total finance lease costs		5.3	4.9	10.6	9.4
Depreciation and Amortization
Lease Cost [Line Items]
Amortization of leased assets		3.6	3.4	7.2	6.5
Interest Expense
Lease Cost [Line Items]
Interest on lease liabilities		1.7	1.5	3.4	2.9
Equipment | Utilities and Other
Lease Cost [Line Items]
Total operating lease costs	[1]	1.2	0.8	2.1	1.6
Real Estate | Facility Lease Expense
Lease Cost [Line Items]
Total operating lease costs	[1]	$ 84.9	$ 84.0	$ 164.7	$ 164.6

[1] Includes short-term lease payments, variable lease payments and office and equipment lease payments reflected in general and administrative expense as set forth in the following table for the periods presented: