Accrued Loss Reserves (Detail) - USD ($) $ in Thousands	May 31, 2022	May 31, 2021
Schedule Of Accrued Liabilities [Line Items]
Accrued losses	$ 24,508	$ 29,054
Accrued Loss Reserves - Noncurrent	35,935	36,627
Accrued product liability and other loss reserves
Schedule Of Accrued Liabilities [Line Items]
Accrued losses	16,003	18,296
Accrued Loss Reserves - Noncurrent	26,226	26,614
Accrued warranty reserves
Schedule Of Accrued Liabilities [Line Items]
Accrued losses	7,450	9,429
Accrued Loss Reserves - Noncurrent	3,455	3,746
Accrued environmental reserves
Schedule Of Accrued Liabilities [Line Items]
Accrued losses	1,055	1,329
Accrued Loss Reserves - Noncurrent	$ 6,254	$ 6,267