Estimate of Annual Preventable Hospital Deaths Prevented by 2020

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Related Party Transactions (Details) $ in Millions	3 Months Ended		9 Months Ended
Related Party Transactions (Details) $ in Millions	Sep. 29, 2018 USD ($) death	Sep. 30, 2017 USD ($)	Sep. 29, 2018 USD ($) ft² death	Sep. 30, 2017 USD ($)	Dec. 30, 2017 USD ($)
Related Party Transaction [Line Items]
Property Plant and Equipment, Occupied Square Feet \| ft²			16,830
Related Party Transaction, Expenses from Transactions with Related Party	$ 1.0
Estimate of Annual Preventable Hospital Deaths Prevented by 2020 \| death	200,000		200,000
Cercacor Laboratories
Related Party Transaction [Line Items]
Payments for Royalties	$ 3.0	$ 2.1	$ 7.5	$ 5.6
Payment for Administrative Fees	0.1	0.1	0.1	0.1
Operating Leases, Income Statement, Sublease Revenue	0.1	$ 0.1	0.3	$ 0.3
Related Party Transaction, Due from (to) Related Party	2.1		2.1		$ 1.5
Reimbursement Fee
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	$ 0.1		0.2
Masimo Foundation
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party			1.0
Variable Interest Entity, Not Primary Beneficiary [Member] \| Minimum
Related Party Transaction [Line Items]
Payments for Royalties			$ 5.0