Share-based Payments (Compensation Costs) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total compensation costs related to share based payments	$ 26.0	$ 20.0	$ 41.6	$ 35.1
Selling, general and administrative:
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock option compensation expense	0.1	0.8	0.5	2.3
Equity-classified share units	23.5	17.3	35.1	25.6
Liability-classified share units	0.5	0.2	1.3	1.5
Employee share purchase plan	1.7	1.7	4.3	4.6
Total compensation costs related to share based payments	25.8	20.0	41.2	34.0
Acquisition-related and integration costs:
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Acceleration of share-based payments expense	0.0	0.0	0.0	0.9
Share-based continuing employment costs	0.2	0.0	0.4	0.2
Total compensation costs related to share based payments	$ 0.2	$ 0.0	$ 0.4	$ 1.1

Amount of acceleration of share-based payments expense in relation to business combinations.

No definition available.

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- Definition

For transactions that are recognized separately from the acquisition of assets and assumptions of liabilities in the business combination, such as related to pre-existing relationships with the acquiree, this element represents the disclosure of the amount of acquisition related share based continuing employment costs which have been expensed.

+ References

No definition available.

+ Details

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- Definition

Compensation Expense related to the company's contribution to employee stock purchase plan (ESPP).

+ References

No definition available.

+ Details

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- Definition

Compensation expense representing accretion of the fair value of the contingently redeemable performance share units on the grant or modification date over the remaining service period.

+ References

No definition available.

+ Details

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- Definition

The expense that accounts for the value of liability-classified share units distributed to employees as compensation.

+ References

No definition available.

+ Details

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of noncash expense for option under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

+ Details

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- Details

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- Details

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