Capital Stock - Schedule of Share-based Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2025	Jun. 30, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Compensation Expense:	$ 5.2	$ 5.2
Impact of modification for change to cash payment	2.2	0.0
Total share-based compensation expense	7.4	5.2
Restricted share units and other share-based compensation \| Operating Segments
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Compensation Expense:	5.2	4.5
Corporate allocation of share-based compensation \| Segment Reporting, Reconciling Item, Corporate Nonsegment
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Compensation Expense:	$ 0.0	$ 0.7

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors, certain consultants qualifying for treatment as employees, including the impact of compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

No definition available.

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Period Type:	duration

- 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

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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.

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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

+ References

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

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