Summary of Quarterly Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Data [Abstract]
Total revenue	$ 605,446	$ 605,303	$ 620,103	$ 576,056	$ 549,386	$ 545,448	$ 580,752	$ 537,656	$ 2,406,908	$ 2,213,242	$ 1,969,058
Gross profit	331,149	344,950	357,853	331,597	300,361	305,643	332,439	303,099	1,365,549	1,241,542	1,097,382
Operating income	115,631	139,802	164,275	133,138	115,347	117,350	145,594	113,044	552,846	491,335	413,028
Net income attributable to IDEXX Laboratories, Inc. stockholders	$ 90,496	$ 108,837	$ 125,706	$ 102,681	$ 85,638	$ 93,251	$ 108,691	$ 89,451	$ 427,720	$ 377,031	$ 263,144
Earnings per Share:
Basic (in USD per share)	$ 1.05	$ 1.26	$ 1.46	$ 1.19	$ 0.99	$ 1.07	$ 1.25	$ 1.02	$ 4.97	$ 4.34	$ 3.00
Diluted (in USD per share)	$ 1.04	$ 1.24	$ 1.43	$ 1.17	$ 0.98	$ 1.05	$ 1.23	$ 1.01	$ 4.89	$ 4.26	$ 2.94