CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2017	Apr. 01, 2016	Mar. 31, 2017	Apr. 01, 2016
Statement of Comprehensive Income [Abstract]
Net earnings	$ 56.0	$ 97.0	$ 77.0	$ 186.0
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 for the three and six months ended March 31, 2017, respectively, and $0.1 and $0.1 for the corresponding periods of fiscal year 2016, respectively.	(0.1)	0.0	(0.2)	(0.1)
Amortization of net actuarial loss included in net periodic benefit cost, net of tax expense of ($0.2) and ($0.4) for the three and six months ended March 31, 2017, respectively, and ($0.2) and ($0.3) for the corresponding periods of fiscal year 2016, respectively.	0.9	0.6	1.8	1.2
Defined benefit pension and post-retirement benefit plans	0.8	0.6	1.6	1.1
Derivative instruments:
Change in unrealized gain, net of tax benefit of $0.5 for both the three and six months ended April 1, 2016, respectively	0.0	(0.9)	0.0	(0.8)
Reclassification adjustments, net of tax benefit of $0.0 for both the three and six months ended April 1, 2016, respectively	0.0	(0.1)	0.0	(0.1)
Derivative instruments	0.0	(1.0)	0.0	(0.9)
Available-for-sale securities:
Change in unrealized loss, net of tax benefit of $0.1 for the six months ended April 1, 2016, respectively.	0.0	0.0	0.0	(0.3)
Reclassification adjustments, net of tax expense of ($0.2) for the six months ended April 1, 2016, respectively.	0.0	0.0	0.0	0.4
Available-for-sale securities	0.0	0.0	0.0	0.1
Currency translation adjustment	2.9	9.8	(10.2)	5.2
Other comprehensive income (loss)	3.7	9.4	(8.6)	5.5
Comprehensive earnings	59.7	106.4	68.4	191.5
Less: Comprehensive earnings (loss) attributable to noncontrolling interests	(0.1)	0.0	0.5	0.0
Comprehensive earnings attributable to Varian	$ 59.8	$ 106.4	$ 67.9	$ 191.5