Segment Reporting (Summary Of Revenue By Product And Service Category) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Revenue	$ 448,308	$ 406,387	$ 1,332,427	$ 1,202,207
CAG Diagnostics Recurring Revenue [Member]
Segment Reporting Information [Line Items]
Revenue	324,233	290,502	968,041	869,413
IDEXX Vetlab Consumables [Member]
Segment Reporting Information [Line Items]
Revenue	113,963	98,957	336,483	298,093
IDEXX VetLab Service and Accessories [Member]
Segment Reporting Information [Line Items]
Revenue	14,878	13,675	43,461	41,223
Rapid Assay Products [Member]
Segment Reporting Information [Line Items]
Revenue	48,720	47,534	147,583	143,353
Reference Laboratory Diagnostic And Consulting Services [Member]
Segment Reporting Information [Line Items]
Revenue	146,672	130,336	440,514	386,744
CAG Diagnostic Capital - Instruments [Member]
Segment Reporting Information [Line Items]
Revenue	31,625	25,989	87,119	70,166
Veterinary Software, Services and Diagnostic Imaging Systems [Member]
Segment Reporting Information [Line Items]
Revenue	29,430	27,590	87,990	80,653
CAG Segment [Member]
Segment Reporting Information [Line Items]
Revenue	385,288	344,081	1,143,150	1,020,232
Water Segment [Member]
Segment Reporting Information [Line Items]
Revenue	27,862	25,957	79,243	72,706
LPD Segment [Member]
Segment Reporting Information [Line Items]
Revenue	29,799	30,448	93,511	93,777
Other Segment [Member]
Segment Reporting Information [Line Items]
Revenue	$ 5,359	$ 5,901	$ 16,523	$ 15,492