CONSOLIDATED STATEMENTS OF EQUITY - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Capital in Excess of Par Value	Retained Earnings	Accumulated Other Comprehensive Loss	Total Varian Stockholders' Equity	Noncontrolling Interests
Beginning Balance (in shares) at Sep. 26, 2014		101.0
Balance at beginning of period at Sep. 26, 2014	$ 1,616.4	$ 101.0	$ 642.8	$ 931.2	$ (58.6)	$ 1,616.4	$ 0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	412.0			411.5		411.5	0.5
Other comprehensive loss	(27.9)				(27.9)	(27.9)
Issuance of common stock (in shares)		2.1
Issuance of common stock	91.0	$ 2.1	88.9			91.0
Tax benefits from exercises of share-based payment awards	12.6		12.6			12.6
Shares repurchased for tax withholdings on vesting of restricted stock and restricted stock units (in shares)		(0.2)
Shares repurchased for tax withholdings on vesting of restricted stock and restricted stock units	(16.3)	$ (0.2)	(16.1)			(16.3)
Share-based compensation expense	$ 46.3		46.3			46.3
Repurchases of common stock (in shares)	(4.8)	(4.8)
Repurchases of common stock	$ (422.0)	$ (4.8)	(92.3)	(324.9)		(422.0)
Acquisition of MeVis Medical Solutions AG	10.2						10.2
Capital contributions by Noncontrolling interests	4.0						4.0
Ending Balance (in shares) at Oct. 02, 2015		98.1
Balance at end of period at Oct. 02, 2015	1,726.3	$ 98.1	682.2	1,017.8	(86.5)	1,711.6	14.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	402.7
Net earnings, excluding redeemable noncontrolling interest	402.2			402.3		402.3	(0.1)
Other comprehensive loss	(14.3)				(14.3)	(14.3)
Issuance of common stock (in shares)		1.4
Issuance of common stock	61.9	$ 1.4	60.5			61.9
Tax benefits from exercises of share-based payment awards	3.0		3.0			3.0
Shares repurchased for tax withholdings on vesting of restricted stock and restricted stock units (in shares)		(0.1)
Shares repurchased for tax withholdings on vesting of restricted stock and restricted stock units	(11.0)	$ (0.1)	(10.9)			(11.0)
Share-based compensation expense	$ 48.3		48.3			48.3
Repurchases of common stock (in shares)	(5.7)	(5.7)
Repurchases of common stock	$ (461.3)	$ (5.7)	(104.5)	(351.1)		(461.3)
Reclassification of noncontrolling interest in MeVis to redeemable noncontrolling interest	(10.4)						(10.4)
Other	$ (0.5)						(0.5)
Ending Balance (in shares) at Sep. 30, 2016	93.7	93.7
Balance at end of period at Sep. 30, 2016	$ 1,744.2	$ 93.7	678.6	1,069.0	(100.8)	1,740.5	3.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	250.3
Net earnings, excluding redeemable noncontrolling interest	250.2			249.6		249.6	0.6
Other comprehensive loss	32.0				32.0	32.0
Issuance of common stock (in shares)		1.4
Issuance of common stock	70.7	$ 1.4	69.3			70.7
Tax benefits from exercises of share-based payment awards	$ 0.7		0.7			0.7
Shares repurchased for tax withholdings on vesting of restricted stock and restricted stock units (in shares)	(0.1)	(0.1)
Shares repurchased for tax withholdings on vesting of restricted stock and restricted stock units	$ (10.7)	$ (0.1)	(10.6)			(10.7)
Share-based compensation expense	$ 40.8		40.8			40.8
Repurchases of common stock (in shares)	(3.3)	(3.3)
Repurchases of common stock	$ (294.5)	$ (3.3)	(62.7)	(228.5)		(294.5)
Distribution of Varex	$ (334.1)			(334.1)		(334.1)
Ending Balance (in shares) at Sep. 29, 2017	91.7	91.7
Balance at end of period at Sep. 29, 2017	$ 1,499.3	$ 91.7	$ 716.1	$ 756.0	$ (68.8)	$ 1,495.0	$ 4.3