Revenue Recognition (Disaggregation of Revenue by Major Product and Service Categories) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Total revenue	$ 626,336	$ 576,056
CAG segment revenue
Disaggregation of Revenue [Line Items]
Total revenue	551,996	508,918
Water segment revenue
Disaggregation of Revenue [Line Items]
Total revenue	34,149	30,310
LPD segment revenue
Disaggregation of Revenue [Line Items]
Total revenue	34,154	31,506
Other segment revenue
Disaggregation of Revenue [Line Items]
Total revenue	6,037	5,322
Cag Diagnostics recurring revenue | CAG segment revenue
Disaggregation of Revenue [Line Items]
Total revenue	487,925	443,791
IDEXX VetLab consumables | CAG segment revenue
Disaggregation of Revenue [Line Items]
Total revenue	188,713	167,211
Rapid assay products | CAG segment revenue
Disaggregation of Revenue [Line Items]
Total revenue	57,430	54,431
Reference laboratory diagnostic and consulting services | CAG segment revenue
Disaggregation of Revenue [Line Items]
Total revenue	220,261	202,658
CAG Diagnostics services and accessories | CAG segment revenue
Disaggregation of Revenue [Line Items]
Total revenue	21,521	19,491
CAG Diagnostics capital - instruments | CAG segment revenue
Disaggregation of Revenue [Line Items]
Total revenue	23,833	28,749
Veterinary software, services and diagnostic imaging systems | CAG segment revenue
Disaggregation of Revenue [Line Items]
Total revenue	$ 40,238	$ 36,378