Condensed Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 108,680	$ 85,407	$ 198,156	$ 154,465
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(21,492)	7,954	(16,327)	15,968
Unrealized gain (loss) on net investment hedge	4,479	(3,767)	2,263	(4,860)
Unrealized gain on investments, net of tax expense of $9 and $49 in 2018 and $49 and $23 in 2017	32	125	150	86
Unrealized gain (loss) on derivative instruments:
Unrealized gain (loss), net of tax expense (benefit) of $2,161 and $1,784 in 2018 and $(2,287) and $(3,199) in 2017	8,174	(3,848)	5,786	(5,382)
Reclassification adjustment for losses (gains) included in net income, net of tax benefit (expense) of $379 and $629 in 2018 and $(280) and $(681) in 2017	454	(473)	2,039	(1,147)
Unrealized gain (loss) on derivative instruments	8,628	(4,321)	7,825	(6,529)
Other comprehensive (loss) gain, net of tax	(8,353)	(9)	(6,089)	4,665
Comprehensive income	100,327	85,398	192,067	159,130
Less: comprehensive (loss) income attributable to noncontrolling interest	(11)	50	14	89
Comprehensive income attributable to IDEXX Laboratories, Inc.	$ 100,338	$ 85,348	$ 192,053	$ 159,041