Revenue Recognition - Summary of Disaggregated Revenue (Detail) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2024	May 31, 2023	May 31, 2022
Disaggregation of Revenue [Line Items]
Revenues, net	$ 924,222	$ 822,447	$ 527,159
Food Safety
Disaggregation of Revenue [Line Items]
Revenues, net	655,341	546,797	259,979
Food Safety | Natural Toxins, Allergens & Drug Residues
Disaggregation of Revenue [Line Items]
Revenues, net	82,240	82,567	79,395
Food Safety | Bacterial & General Sanitation
Disaggregation of Revenue [Line Items]
Revenues, net	171,217	134,934	47,282
Food Safety | Indicator Testing, Culture Media And Other
Disaggregation of Revenue [Line Items]
Revenues, net	334,636	267,178	75,278
Food Safety | Rodenticides, Insecticides & Disinfectants
Disaggregation of Revenue [Line Items]
Revenues, net	42,965	39,655	35,691
Food Safety | Genomics Services
Disaggregation of Revenue [Line Items]
Revenues, net	24,283	22,463	22,333
Animal Safety
Disaggregation of Revenue [Line Items]
Revenues, net	268,881	275,650	267,180
Animal Safety | Life Sciences
Disaggregation of Revenue [Line Items]
Revenues, net	6,515	6,254	5,685
Animal Safety | Animal Care & Other
Disaggregation of Revenue [Line Items]
Revenues, net	36,978	39,068	39,805
Animal Safety | Veterinary Instruments & Disposables
Disaggregation of Revenue [Line Items]
Revenues, net	65,848	63,843	63,938
Animal Safety | Rodenticides, Insecticides & Disinfectants
Disaggregation of Revenue [Line Items]
Revenues, net	88,732	87,423	83,610
Animal Safety | Genomics Services
Disaggregation of Revenue [Line Items]
Revenues, net	$ 70,808	$ 79,062	$ 74,142