EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Apr. 03, 2020	Mar. 29, 2019	Apr. 03, 2020	Mar. 29, 2019
Earnings Per Share [Abstract]
Net earnings	$ 43.1	$ 88.4	$ 132.0	$ 192.3
Less: Net earnings (loss) attributable to noncontrolling interests	(0.1)	(0.2)	0.6	0.5
Net earnings attributable to Varian	$ 43.2	$ 88.6	$ 131.4	$ 191.8
Weighted average shares outstanding - basic (in shares)	90.7	91.0	90.8	91.0
Dilutive effect of potential common shares (in shares)	0.7	0.9	0.8	1.0
Weighted average shares outstanding - diluted (in shares)	91.4	91.9	91.6	92.0
Net earnings per share attributable to Varian - basic (in dollars per share)	$ 0.48	$ 0.97	$ 1.45	$ 2.11
Net earnings per share attributable to Varian - diluted (in dollars per share)	$ 0.47	$ 0.96	$ 1.43	$ 2.09
Anti-dilutive employee shared based awards, excluded (in shares)	1.1	0.5	1.1	1.0