Revenue Recognition - Summary of Disaggregated Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Feb. 29, 2024	Feb. 28, 2023	Feb. 29, 2024	Feb. 28, 2023
Disaggregation of Revenue [Line Items]
Total Revenues, net	$ 228,812	$ 218,255	$ 687,428	$ 580,637
Food Safety
Disaggregation of Revenue [Line Items]
Total Revenues, net	157,754	151,542	488,435	377,528
Food Safety | Natural Toxins & Allergens
Disaggregation of Revenue [Line Items]
Total Revenues, net	19,738	19,198	63,116	61,236
Food Safety | Bacterial & General Sanitation
Disaggregation of Revenue [Line Items]
Total Revenues, net	40,395	39,444	128,393	91,293
Food Safety | Indicator Testing, Culture Media & Other
Disaggregation of Revenue [Line Items]
Total Revenues, net	81,168	77,955	246,812	179,293
Food Safety | Rodenticides, Insecticides & Disinfectants
Disaggregation of Revenue [Line Items]
Total Revenues, net	10,136	9,550	32,180	29,502
Food Safety | Genomics Services
Disaggregation of Revenue [Line Items]
Total Revenues, net	6,317	5,395	17,934	16,204
Animal Safety
Disaggregation of Revenue [Line Items]
Total Revenues, net	71,058	66,713	198,993	203,109
Animal Safety | Rodenticides, Insecticides & Disinfectants
Disaggregation of Revenue [Line Items]
Total Revenues, net	23,055	20,242	65,694	63,121
Animal Safety | Genomics Services
Disaggregation of Revenue [Line Items]
Total Revenues, net	18,589	20,868	53,518	59,168
Animal Safety | Life Sciences
Disaggregation of Revenue [Line Items]
Total Revenues, net	1,372	1,440	4,710	4,456
Animal Safety | Veterinary Instruments & Disposables
Disaggregation of Revenue [Line Items]
Total Revenues, net	17,976	15,428	47,845	46,534
Animal Safety | Animal Care & Other
Disaggregation of Revenue [Line Items]
Total Revenues, net	$ 10,066	$ 8,735	$ 27,226	$ 29,830