Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 427,792	$ 377,047	$ 263,269
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(1,590)	(21,911)	25,107
Unrealized gain (loss) on Euro-denominated notes, net of tax expense (benefit) of $564 in 2019, $1,148 in 2018 and ($4,555) in 2017	1,790	3,917	(8,347)
Unrealized gain (loss) on investments, net of tax expense (benefit) of $84 in 2019, ($40) in 2018 and $0 in 2017	267	(135)	(42)
Unrealized gain (loss) on derivative instruments:
Unrealized gain (loss) on foreign currency exchange contracts, net of tax expense (benefit) of $362 in 2019, $2,529 in 2018 and ($5,304) in 2017	1,196	10,659	(10,332)
Unrealized gain on cross currency swaps, net of tax expense of $664 in 2019, $323 in 2018 and $0 in 2017	2,107	1,360	0
Less: reclassification adjustment for (gains) losses included in net income, net of tax (expense) benefit of ($2,467) in 2019, $187 in 2018 and $224 in 2017	(8,161)	789	197
Unrealized (loss) gain on derivative instruments	(4,858)	12,808	(10,135)
Other comprehensive (loss) gain, net of tax	(4,391)	(5,321)	6,583
Comprehensive income	423,401	371,726	269,852
Less: comprehensive income attributable to noncontrolling interest	72	16	125
Comprehensive income attributable to IDEXX Laboratories, Inc.	$ 423,329	$ 371,710	$ 269,727