CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2019	Sep. 28, 2018	Sep. 29, 2017
Statement of Comprehensive Income [Abstract]
Net earnings	$ 292.2	$ 150.3	$ 219.2
Defined benefit pension and post-retirement benefit plans:
Net gain (loss) arising during the year, net of tax benefit (expense) of $4.5, ($1.1), and ($2.5)	(27.8)	4.7	10.0
Prior service credit (cost) arising during the year, net of tax benefit (expense) of $0.1, ($0.3), and ($0.7)	(0.7)	1.9	4.3
Amortization of prior service cost included in net periodic benefit cost, net of tax benefit of $0.1, $0.2, and $0.2	(0.7)	(1.0)	(0.8)
Amortization, settlement and curtailment of net actuarial loss included in net periodic benefit cost, net of tax expense of ($0.4), ($0.6), and ($1.0)	2.7	3.3	5.7
Defined benefit pension and post-retirement benefit plans	(26.5)	8.9	19.2
Derivative instruments:
Change in unrealized gain (loss), net of tax benefit (expense) of ($0.7), $0.3, and $0.0	2.3	(0.6)	0.0
Reclassification adjustments, net of tax benefit (expense) of $0.0, ($0.3), and $0.0	(0.2)	0.6	0.0
Derivative Instruments	2.1	0.0	0.0
Currency translation adjustment	(12.4)	(5.4)	12.8
Other comprehensive earnings (loss)	(36.8)	3.5	32.0
Comprehensive earnings	255.4	153.8	251.2
Less: Comprehensive earnings attributable to noncontrolling interests	0.3	0.4	0.7
Comprehensive earnings attributable to Varian	$ 255.1	$ 153.4	$ 250.5