Segment Reporting (Summary Of Revenue By Product And Service Category) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Segment Reporting Information [Line Items]
Revenue	$ 360,203	$ 332,106
CAG Diagnostics Recurring Revenue [Member]
Segment Reporting Information [Line Items]
Revenue	258,763	239,568
IDEXX VetLab Consumables [Member]
Segment Reporting Information [Line Items]
Revenue	84,321	75,783
VetLab Service and Accessories [Member]
Segment Reporting Information [Line Items]
Revenue	13,093	12,053
Rapid Assay Products [Member]
Segment Reporting Information [Line Items]
Revenue	43,059	44,083
Reference Laboratory Diagnostic And Consulting Services [Member]
Segment Reporting Information [Line Items]
Revenue	118,290	107,649
CAG Diagnostic Capital - Instruments [Member]
Segment Reporting Information [Line Items]
Revenue	18,565	15,835
Customer Information Managment and Digital Imaging Systems [Member]
Segment Reporting Information [Line Items]
Revenue	24,260	21,538
CAG Segment [Member]
Segment Reporting Information [Line Items]
Revenue	301,588	276,941
Water Segment [Member]
Segment Reporting Information [Line Items]
Revenue	21,421	20,666
LPD Segment [Member]
Segment Reporting Information [Line Items]
Revenue	31,351	28,039
Other Segment [Member]
Segment Reporting Information [Line Items]
Revenue	$ 5,843	$ 6,460