v3.25.4

Segment Information - Segment Breakdown of Goodwill (Detail) - USD ($) $ in Thousands	Dec. 31, 2025	Mar. 31, 2025
Segment Reporting Information [Line Items]
Goodwill	$ 470,672	$ 469,894
Cement [Member]
Segment Reporting Information [Line Items]
Goodwill	227,639	227,639
Concrete and Aggregates [Member]
Segment Reporting Information [Line Items]
Goodwill	118,877	118,099
Gypsum Wallboard [Member]
Segment Reporting Information [Line Items]
Goodwill	116,618	116,618
Recycled Paperboard [Member]
Segment Reporting Information [Line Items]
Goodwill	$ 7,538	$ 7,538

X

- Definition

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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