CONDENSED CONSOLIDATED STATEMENTS OF EQUITY Statement - 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. 28, 2018		91.2
Balance at beginning of period at Sep. 28, 2018	$ 1,588.7	$ 91.2	$ 778.1	$ 780.4	$ (65.3)	$ 1,584.4	$ 4.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	103.9			103.2		103.2	0.7
Other comprehensive earnings (loss)	(3.7)				(3.7)	(3.7)
Issuance of common stock (in shares)		0.3
Issuance of common stock	22.0	$ 0.3	21.7			22.0
Tax withholdings on vesting of equity awards	(4.4)		(4.4)			(4.4)
Share-based compensation expense	10.5		10.5			10.5
Repurchases of common stock (in shares)		(0.3)
Repurchases of common stock	(34.8)	$ (0.3)	(6.6)	(27.9)		(34.8)
Other	(0.2)		0.0	(0.2)		(0.2)
Ending balance (in shares) at Dec. 28, 2018		91.2
Balance at end of period at Dec. 28, 2018	1,682.0	$ 91.2	799.3	855.5	(69.0)	1,677.0	5.0
Beginning balance (in shares) at Sep. 28, 2018		91.2
Balance at beginning of period at Sep. 28, 2018	1,588.7	$ 91.2	778.1	780.4	(65.3)	1,584.4	4.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive earnings (loss)	$ (6.5)
Repurchases of common stock (in shares)	(0.7)
Ending balance (in shares) at Mar. 29, 2019		91.2
Balance at end of period at Mar. 29, 2019	$ 1,740.1	$ 91.2	813.6	902.3	(71.8)	1,735.3	4.8
Beginning balance (in shares) at Dec. 28, 2018		91.2
Balance at beginning of period at Dec. 28, 2018	1,682.0	$ 91.2	799.3	855.5	(69.0)	1,677.0	5.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	88.4			88.6		88.6	(0.2)
Other comprehensive earnings (loss)	(2.8)				(2.8)	(2.8)
Issuance of common stock (in shares)		0.5
Issuance of common stock	20.3	$ 0.5	19.8			20.3
Tax withholdings on vesting of equity awards (shares)		(0.1)
Tax withholdings on vesting of equity awards	(9.5)	$ (0.1)	(9.4)			(9.5)
Share-based compensation expense	$ 12.5		12.5			12.5
Repurchases of common stock (in shares)	(0.4)	(0.4)
Repurchases of common stock	$ (50.8)	$ (0.4)	(8.6)	(41.8)		(50.8)
Ending balance (in shares) at Mar. 29, 2019		91.2
Balance at end of period at Mar. 29, 2019	$ 1,740.1	$ 91.2	813.6	902.3	(71.8)	1,735.3	4.8
Beginning balance (in shares) at Sep. 27, 2019	90.8	90.8
Balance at beginning of period at Sep. 27, 2019	$ 1,777.6	$ 90.8	845.6	934.0	(102.1)	1,768.3	9.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	88.9			88.2		88.2	0.7
Other comprehensive earnings (loss)	5.1				5.1	5.1
Issuance of common stock (in shares)		0.3
Issuance of common stock	$ 21.0	$ 0.3	20.7			21.0
Tax withholdings on vesting of equity awards (shares)	0.0
Tax withholdings on vesting of equity awards	$ (3.6)	$ 0.0	(3.6)			(3.6)
Share-based compensation expense	14.7		14.7			14.7
Repurchases of common stock (in shares)		(0.4)
Repurchases of common stock	(46.4)	$ (0.4)	(7.0)	(39.0)		(46.4)
Ending balance (in shares) at Jan. 03, 2020		90.7
Balance at end of period at Jan. 03, 2020	$ 1,857.3	$ 90.7	870.4	983.2	(97.0)	1,847.3	10.0
Beginning balance (in shares) at Sep. 27, 2019	90.8	90.8
Balance at beginning of period at Sep. 27, 2019	$ 1,777.6	$ 90.8	845.6	934.0	(102.1)	1,768.3	9.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive earnings (loss)	$ 0.3
Repurchases of common stock (in shares)	(0.6)
Ending balance (in shares) at Apr. 03, 2020	90.7	90.7
Balance at end of period at Apr. 03, 2020	$ 1,870.7	$ 90.7	878.2	993.7	(101.8)	1,860.8	9.9
Beginning balance (in shares) at Jan. 03, 2020		90.7
Balance at beginning of period at Jan. 03, 2020	1,857.3	$ 90.7	870.4	983.2	(97.0)	1,847.3	10.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	43.1			43.2		43.2	(0.1)
Other comprehensive earnings (loss)	(4.8)				(4.8)	(4.8)
Issuance of common stock (in shares)		0.3
Issuance of common stock	11.3	$ 0.3	11.0			11.3
Tax withholdings on vesting of equity awards (shares)		0.0
Tax withholdings on vesting of equity awards	(7.9)	$ 0.0	(7.9)			(7.9)
Share-based compensation expense	$ 11.5		11.5			11.5
Repurchases of common stock (in shares)	(0.3)	(0.3)
Repurchases of common stock	$ (39.8)	$ (0.3)	(6.8)	(32.7)		(39.8)
Ending balance (in shares) at Apr. 03, 2020	90.7	90.7
Balance at end of period at Apr. 03, 2020	$ 1,870.7	$ 90.7	$ 878.2	$ 993.7	$ (101.8)	$ 1,860.8	$ 9.9