ACQUISITION AND RELATED PARTY ITEMS - Unaudited Pro Forma Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Scil Animal Care Company
Business Acquisition [Line Items]
Revenue, net	$ 49,346	$ 151,522	$ 144,372
Net (loss) income before equity in losses of unconsolidated affiliates	(451)	(17,733)	(1,407)
Net (loss) income attributable to Heska Corporation	(557)	$ (17,680)	(1,730)
CVM
Business Acquisition [Line Items]
Revenue, net	32,910		94,462
Net (loss) income before equity in losses of unconsolidated affiliates	164		789
Net (loss) income attributable to Heska Corporation	$ 58		$ 466