Discontinued Operations - Disposal Group's Assets and Liabilities Presented as Held for Sale (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Current assets
Cash and cash equivalents	$ 0.0	$ 1.3	$ 1.7
Total current assets from discontinued operations	0.0	460.0
Total noncurrent assets from discontinued operations	0.0	570.2
Current liabilities
Total current liabilities from discontinued operations	0.0	338.5
Total noncurrent liabilities from discontinued operations	$ 0.0	85.7
Disposal Group [Member]
Current assets
Cash and cash equivalents		1.3
Receivables, less allowances of $2.9		400.9
Inventory, materials and supplies		18.8
Prepaid expenses		27.6
Other current assets		11.4
Total current assets from discontinued operations		460.0
Property, plant and equipment, net		73.4
Goodwill		154.3
Intangible assets, net		300.2
Deferred income tax assets		2.8
Other noncurrent assets		39.5
Total noncurrent assets from discontinued operations		570.2
Total assets from discontinued operations		1,030.2
Current liabilities
Current portion of long-term debt		6.7
Accounts payable		264.9
Unearned revenue and customer deposits		25.3
Accrued taxes		4.3
Accrued payroll and benefits		16.5
Other current liabilities		20.8
Total current liabilities from discontinued operations		338.5
Long-term debt, less current portion		6.3
Deferred income tax liability		52.3
Other noncurrent liabilities		27.1
Total noncurrent liabilities from discontinued operations		85.7
Total liabilities from discontinued operations		$ 424.2