Segment Information - Depreciation and Amortization (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Segment Reporting [Line Items]
Depreciation and amortization	$ 168.8	$ 56.5
Operating Segments \| Siding & Trim
Segment Reporting [Line Items]
Depreciation and amortization	68.5	43.6
Operating Segments \| Deck, Rail & Accessories
Segment Reporting [Line Items]
Depreciation and amortization	80.9	0.0
Operating Segments \| Australia & New Zealand
Segment Reporting [Line Items]
Depreciation and amortization	6.7	5.2
Operating Segments \| Europe
Segment Reporting [Line Items]
Depreciation and amortization	10.2	6.8
General Corporate and R&D
Segment Reporting [Line Items]
Depreciation and amortization	$ 2.5	$ 0.9

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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+ Details

- 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.

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+ Details