Revenue (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Mar. 29, 2020	Dec. 29, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 30, 2018	Sep. 30, 2018	Jul. 01, 2018	Apr. 01, 2018	Dec. 31, 2017	Oct. 01, 2017	Jul. 02, 2017	Mar. 29, 2020	Mar. 31, 2019	Apr. 01, 2018
Disaggregation of Revenue [Line Items]
Sales	$ 132,413	$ 120,406	$ 140,043	$ 147,336	$ 133,051	$ 128,151	$ 145,324	$ 149,800	$ 126,990	$ 118,053	$ 125,395	$ 133,731	$ 540,198	$ 556,326	$ 504,169
Industrial [Member]
Disaggregation of Revenue [Line Items]
Sales													275,224	281,860	247,374
Water Treatment [Member]
Disaggregation of Revenue [Line Items]
Sales													159,895	149,490	138,465
Health and Nutrition [Member]
Disaggregation of Revenue [Line Items]
Sales													105,079	124,976	$ 118,330
Bulk / Distributed specialty products [Member]
Disaggregation of Revenue [Line Items]
Sales													158,410	191,827
Bulk / Distributed specialty products [Member] | Industrial [Member]
Disaggregation of Revenue [Line Items]
Sales													49,864	60,947
Bulk / Distributed specialty products [Member] | Water Treatment [Member]
Disaggregation of Revenue [Line Items]
Sales													18,481	21,813
Bulk / Distributed specialty products [Member] | Health and Nutrition [Member]
Disaggregation of Revenue [Line Items]
Sales													90,065	109,067
Manufactured, blended or repackaged products [Member]
Disaggregation of Revenue [Line Items]
Sales													376,848	358,775
Manufactured, blended or repackaged products [Member] | Industrial [Member]
Disaggregation of Revenue [Line Items]
Sales													222,161	216,874
Manufactured, blended or repackaged products [Member] | Water Treatment [Member]
Disaggregation of Revenue [Line Items]
Sales													139,917	126,217
Manufactured, blended or repackaged products [Member] | Health and Nutrition [Member]
Disaggregation of Revenue [Line Items]
Sales													14,770	15,684
Other [Member]
Disaggregation of Revenue [Line Items]
Sales													4,940	5,724
Other [Member] | Industrial [Member]
Disaggregation of Revenue [Line Items]
Sales													3,199	4,039
Other [Member] | Water Treatment [Member]
Disaggregation of Revenue [Line Items]
Sales													1,497	1,460
Other [Member] | Health and Nutrition [Member]
Disaggregation of Revenue [Line Items]
Sales													$ 244	$ 225