Condensed Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Condensed Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 89,476	$ 69,058
Other comprehensive income, net of tax:
Foreign currency translation adjustments	5,165	8,014
Unrealized loss on net investment hedge	(2,216)	(1,093)
Unrealized gain (loss) on investments, net of tax expense (benefit) of $40 in 2018 and $(26) in 2017	118	(39)
Unrealized loss on derivative instruments:
Unrealized loss, net of tax (benefit) of $(377) in 2018 and $(912) in 2017	(2,388)	(1,534)
Reclassification adjustment for losses (gains) included in net income, net of tax (benefit) expense of $(250) in 2018 and $401 in 2017	1,585	(674)
Unrealized loss on derivative instruments	(803)	(2,208)
Other comprehensive gain, net of tax	2,264	4,674
Comprehensive income	91,740	73,732
Less: comprehensive income attributable to noncontrolling interest	25	39
Comprehensive income attributable to IDEXX Laboratories, Inc.	$ 91,715	$ 73,693