Segment and Geographical Area Information (External Revenue and Long-Lived Assets) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items]
External revenue	$ 663.2	$ 605.1	$ 1,308.0	$ 1,187.0
Long-lived assets	239.6		239.6		$ 231.9
United States
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items]
External revenue	479.1	431.6	941.1	856.1
Long-lived assets	178.2		178.2		178.6
Total International
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items]
External revenue	184.1	173.5	366.9	330.9
Long-lived assets	61.4		61.4		53.3
Canada
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items]
External revenue	47.3	48.2	96.5	91.9
Long-lived assets	4.7		4.7		4.9
Continental Europe
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items]
External revenue	55.0	55.0	112.0	105.6
Long-lived assets	5.3		5.3		6.3
Australia
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items]
External revenue	19.4	16.2	37.5	31.3
Long-lived assets	0.9		0.9		1.1
Canada
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items]
External revenue	46.6	38.6	89.3	71.7
Long-lived assets	18.4		18.4		17.9
United Kingdom
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items]
External revenue	12.1	12.2	23.9	24.1
Long-lived assets	32.0		32.0		22.8
Other
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items]
External revenue	3.7	$ 3.3	7.7	$ 6.3
Long-lived assets	$ 0.1		$ 0.1		$ 0.3