CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (LOSS) - USD ($) $ in Millions		3 Months Ended
		Dec. 28, 2018	Dec. 29, 2017
Statement of Comprehensive Income [Abstract]
Net earnings (loss)		$ 103.9	$ (112.2)
Defined benefit pension and post-retirement benefit plans:
Amortization of prior service cost included in net periodic benefit cost, net of tax benefit of $0.0 and $0.1, respectively	[1]	(0.2)	(0.2)
Amortization of net actuarial loss included in net periodic benefit cost, net of tax expense of ($0.1) and ($0.2), respectively		0.5	0.5
Defined benefit pension and post-retirement benefit plans		0.3	0.3
Derivative instruments:
Change in unrealized loss, net of tax benefit of $0.0 and $0.1, respectively		0.0	(0.2)
Reclassification adjustments, net of tax expense of $0.0 and $0.0, respectively	[1]	0.0	(0.1)
Derivative instruments		0.0	(0.3)
Currency translation adjustment		(4.0)	3.1
Other comprehensive (loss) earnings		(3.7)	3.1
Comprehensive earnings (loss)		100.2	(109.1)
Less: Comprehensive earnings attributable to noncontrolling interests		0.7	0.1
Comprehensive earnings (loss) attributable to Varian		$ 99.5	$ (109.2)

[1] Tax expense or benefit related to the periods presented are not material.