CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Income Statement [Abstract]
Revenues	$ 1,026.1	$ 1,066.4	$ 2,009.7	$ 2,115.5
Type of Revenue	us-gaap:ServiceMember	us-gaap:ServiceMember	us-gaap:ServiceMember	us-gaap:ServiceMember
Expenses:
Cost of services	$ 642.8	$ 663.9	$ 1,262.0	$ 1,305.2
Type of Cost of Service	us-gaap:ServiceMember	us-gaap:ServiceMember	us-gaap:ServiceMember	us-gaap:ServiceMember
Selling, general, and administrative	$ 190.6	$ 211.8	$ 377.6	$ 427.5
Total expenses	833.4	875.7	1,639.6	1,732.7
Operating income	192.7	190.7	370.1	382.8
Other income/(expense):
Interest income	1.8	3.7	3.5	6.8
Interest expense	(36.7)	(31.1)	(69.3)	(57.2)
Other income, net	1.9	1.9	2.7	2.8
Total other expense, net	(33.0)	(25.5)	(63.1)	(47.6)
Income before income taxes	159.7	165.2	307.0	335.2
Provision for income taxes	37.6	24.2	61.4	51.5
Net income	$ 122.1	$ 141.0	$ 245.6	$ 283.7
Earnings per share:
Basic (USD per share)	$ 0.37	$ 0.42	$ 0.74	$ 0.83
Diluted (USD per share)	$ 0.37	$ 0.41	$ 0.73	$ 0.83
Weighted-average shares outstanding:
Basic (shares)	328.9	338.6	333.3	341.5
Diluted (shares)	329.6	339.6	334.4	342.6

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

Name:	us-gaap_CostOfGoodsAndServicesSold
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Total costs of sales and operating expenses for the period.