Business Segment Information - Business Segment Net Sales (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Oct. 31, 2020	Jul. 31, 2020	Apr. 30, 2020	Jan. 31, 2020	Oct. 31, 2019	Jul. 31, 2019	Apr. 30, 2019	Jan. 31, 2019	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2018
Segment Reporting Information [Line Items]
Net sales	$ 681.6	$ 578.2	$ 524.9	$ 646.2	$ 691.6	$ 679.4	$ 654.3	$ 628.1	$ 2,430.9	$ 2,653.4	$ 2,532.8
CooperVision
Segment Reporting Information [Line Items]
Net sales									1,843.0	1,972.9	1,882.0
CooperSurgical
Segment Reporting Information [Line Items]
Net sales									587.9	680.5	650.8
Toric lens | CooperVision
Segment Reporting Information [Line Items]
Net sales									598.2	620.0	591.4
Multifocal lens | CooperVision
Segment Reporting Information [Line Items]
Net sales									197.0	202.9	196.6
Single-use sphere lens | CooperVision
Segment Reporting Information [Line Items]
Net sales									529.0	568.2	520.1
Non single-use sphere, other | CooperVision
Segment Reporting Information [Line Items]
Net sales									518.8	581.8	573.9
Office and surgical products | CooperSurgical
Segment Reporting Information [Line Items]
Net sales									358.8	422.4	400.4
Fertility | CooperSurgical
Segment Reporting Information [Line Items]
Net sales									$ 229.1	$ 258.1	$ 250.4