EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share [Abstract]
Net (loss) income attributable to Heska Corporation	$ (567)	$ (6,357)	$ 1,304	$ (11,645)
Basic weighted-average common shares outstanding (in shares)	10,167	8,776	9,825	8,165
Dilutive effect of stock options and restricted stock awards	0	0	364	0
Diluted weighted-average common shares outstanding	10,167	8,776	10,189	8,165
Basic (loss) earnings per share attributable to Heska Corporation (in dollars per share)	$ (0.06)	$ (0.72)	$ 0.13	$ (1.43)
Diluted (loss) earnings per share attributable to Heska Corporation (in dollars per share)	$ (0.06)	$ (0.72)	$ 0.13	$ (1.43)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock options and restricted units excluded from computation of earnings per share	1,370	687	1,002	1,240
Convertible Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock options and restricted units excluded from computation of earnings per share	0	332	0	920
Senior Convertible Note
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock options and restricted units excluded from computation of earnings per share	996	0	996	21
Stock Options And Restricted Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock options and restricted units excluded from computation of earnings per share	374	355	6	299