CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (LOSS) - USD ($) $ in Millions	3 Months Ended
	Dec. 29, 2017	Dec. 30, 2016
Statement of Comprehensive Income [Abstract]
Net earnings (loss)	$ (112.2)	$ 14.5
Defined benefit pension and post-retirement benefit plans:
Amortization of prior service cost included in net periodic benefit cost, net of tax benefit of $0.1 and $0.1	(0.2)	(0.1)
Amortization of net actuarial loss included in net periodic benefit cost, net of tax expense of ($0.2) and ($0.2)	0.5	0.9
Defined benefit pension and post-retirement benefit plans	0.3	0.8
Derivative instruments:
Change in unrealized loss, net of tax benefit of $0.1 and $0.0	(0.2)	0.0
Reclassification adjustments, net of tax expense of $0.0 and $0.0	(0.1)	0.0
Derivative instruments	(0.3)	0.0
Currency translation adjustment	3.1	(13.1)
Other comprehensive earnings (loss)	3.1	(12.3)
Comprehensive earnings (loss)	(109.1)	2.2
Less: Comprehensive earnings attributable to noncontrolling interests	0.1	0.6
Comprehensive earnings (loss) attributable to Varian	$ (109.2)	$ 1.6