Segment Reporting - Summary of Segment Performance (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Revenue	$ 637,592		$ 620,103		$ 1,263,928	$ 1,196,159
Income (loss) from operations	193,248		164,275		337,573	297,413
Interest expense, net	(9,426)		(8,153)		(16,978)	(16,499)
Income before provision for income taxes	183,822		156,122		320,595	280,914
Provision for income taxes	34,826		30,421		59,743	52,504
Net income	148,996	$ 111,856	125,701	$ 102,709	260,852	228,410
Less: Net income attributable to noncontrolling interest	56		(5)		85	23
Net income attributable to IDEXX Laboratories, Inc. stockholders	148,940		125,706		260,767	228,387
CAG
Segment Reporting Information [Line Items]
Revenue	566,100		547,349		1,118,096	1,056,267
Water
Segment Reporting Information [Line Items]
Revenue	28,116		34,764		62,265	65,074
LPD
Segment Reporting Information [Line Items]
Revenue	32,244		33,104		66,398	64,610
Other
Segment Reporting Information [Line Items]
Revenue	11,132		4,886		17,169	10,208
Operating Segments | CAG
Segment Reporting Information [Line Items]
Revenue	566,100		547,349		1,118,096	1,056,267
Income (loss) from operations	167,969		141,190		286,628	252,909
Operating Segments | Water
Segment Reporting Information [Line Items]
Revenue	28,116		34,764		62,265	65,074
Income (loss) from operations	12,258		16,722		28,140	30,537
Operating Segments | LPD
Segment Reporting Information [Line Items]
Revenue	32,244		33,104		66,398	64,610
Income (loss) from operations	8,249		6,568		17,912	12,857
Operating Segments | Other
Segment Reporting Information [Line Items]
Revenue	11,132		4,886		17,169	10,208
Income (loss) from operations	$ 4,772		$ (205)		$ 4,893	$ 1,110