Share-based Payments (Compensation Costs) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total compensation costs related to share based payments	$ 22.8	$ 10.1	$ 64.4	$ 45.2
Selling, general and administrative:
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock option compensation expense	0.1	0.7	0.6	3.0
Equity-classified share units	19.9	7.3	55.0	32.9
Liability-classified share units	0.4	0.6	1.7	2.1
Employee share purchase plan	1.4	1.2	5.7	5.8
Total compensation costs related to share based payments	21.8	9.8	63.0	43.8
Acquisition-related and integration costs:
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Acceleration of share-based payments expense	0.0	0.1	0.0	1.0
Share-based continuing employment costs	1.0	0.2	1.4	0.4
Total compensation costs related to share based payments	$ 1.0	$ 0.3	$ 1.4	$ 1.4

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.

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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.

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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 S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479983/718-10-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-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 3: 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

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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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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)
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-Topic 230
-Publisher FASB
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