EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Jan. 01, 2021	Jan. 03, 2020
Earnings Per Share [Abstract]
Net earnings	$ 96.8	$ 88.9
Less: Net earnings attributable to noncontrolling interests	0.3	0.7
Net earnings attributable to Varian	$ 96.5	$ 88.2
Weighted average shares outstanding - basic (in shares)	91.4	90.9
Dilutive effect of potential common shares (in shares)	0.8	0.8
Weighted average shares outstanding - diluted (in shares)	92.2	91.7
Net earnings per share attributable to Varian - basic (in dollars per share)	$ 1.06	$ 0.97
Net earnings per share attributable to Varian - diluted (in dollars per share)	$ 1.05	$ 0.96
Anti-dilutive employee shared based awards, excluded (in shares)	0.0	0.8