Segments - Net Sales by Main Product Lines (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2025	Jan. 31, 2024	Jan. 31, 2025	Jan. 31, 2024
Revenue from external customers
Total net sales	$ 1,260,710	$ 1,258,348	$ 4,179,942	$ 4,088,878
Wallboard
Revenue from external customers
Total net sales	501,703	520,686	1,671,751	1,677,285
Complementary products
Revenue from external customers
Total net sales	398,647	378,555	1,308,988	1,233,084
Steel framing
Revenue from external customers
Total net sales	179,682	203,363	606,928	672,231
Ceilings
Revenue from external customers
Total net sales	$ 180,678	$ 155,744	$ 592,275	$ 506,278