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Percentage of revenue two customer.

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Royalty Agreement

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Severance plan participation agreements.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

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Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.

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Amount of discretionary contributions made by an employer to a defined contribution plan.

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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

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The minimum amount the entity agreed to spend under the long-term purchase commitment.

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Amount of recurring income classified as other.

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Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

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Commitments and Contingencies - Additional Information - (Detail)			3 Months Ended	12 Months Ended
	Jul. 27, 2017	Jan. 03, 2014 USD ($)	Dec. 30, 2017 USD ($)	Dec. 28, 2019 USD ($) distributor Agreement	Dec. 29, 2018 USD ($) distributor	Dec. 30, 2017 USD ($)
Contingencies And Commitments [Line Items]
Company contribution percentage based on employee contribution of up to 3% of employee's compensation				3.00%
Severance plan participation agreements \| Agreement				8
Supplemental Unemployment Benefits, Severance Benefits, Required Notice of Resignation				6 months
Purchase Commitment, Remaining Minimum Amount Committed				$ 5,000,000.0
License fee, Change in Control				2,500,000
Royalty Guarantees, Commitments, Change in Control				15,000,000.0
Royalty Guarantees, Commitments, Additional, Change in Control				2,000,000.0
Remaining amount committed				108,400,000
Commitments and contingencies
Long-term Purchase Commitment, Amount				47,300,000
Cash and cash equivalents				687,700,000
Short-term investments				120,000,000	0
Cash Equivalents, at Carrying Value				567,700,000
Bank balance covered by Federal Deposit Insurance Corporation limit				$ 3,800,000
Royalty Agreement				1
Royalty				$ 700,000	26,400,000	$ 32,800,000
NRE Service Agreement				1
Other Recurring Income				$ 700,000	2,000,000.0	19,200,000
Litigation settlement, award and/or defense costs				$ 0	$ 425,000	$ 0
Pulse oximetry products
Contingencies And Commitments [Line Items]
Percentage of Revenue - Customer Concentration				55.30%	56.70%	56.50%
Masimo vs Former Agency Tender
Contingencies And Commitments [Line Items]
Litigation settlement, award and/or defense costs			$ 10,500,000
Proceeds from Legal Settlements				$ 2,000,000.0
Masimo vs. Physicians Healthsource, Inc.
Contingencies And Commitments [Line Items]
Damages sought per violation		$ 500
Unsecured Bank Guarantees
Contingencies And Commitments [Line Items]
Commitments and contingencies				$ 2,300,000
Sales
Contingencies And Commitments [Line Items]
Number of just-in-time distributors \| distributor					2
Accounts Receivable
Contingencies And Commitments [Line Items]
Number of just-in-time distributors \| distributor				1
Just in time distributor one \| Revenue Benchmark
Contingencies And Commitments [Line Items]
Percentage Of Revenue Two Customer				13.00%	12.90%	13.70%
Just in time distributor one \| Accounts Receivable
Contingencies And Commitments [Line Items]
Percentage Of Accounts Receivable Balance From Three Just In Time Distributors				6.20%	6.70%
Just in time distributor two \| Revenue Benchmark
Contingencies And Commitments [Line Items]
Percentage Of Revenue Two Customer				11.10%	10.40%	12.10%
United States (U.S.)
Contingencies And Commitments [Line Items]
Company's contribution to employee retirement savings plan				$ 2,500,000	$ 2,300,000	$ 2,200,000
Chief Executive Officer
Contingencies And Commitments [Line Items]
Employment Agreement, Severance Benefits, Special Payment, Qualifying Termination				$ 292,900,000
Chief Executive Officer \| Restricted Stock Units (RSUs)
Contingencies And Commitments [Line Items]
Employment Agreement, Severance Terms	50.00%
Chief Executive Officer \| Cash Distribution
Contingencies And Commitments [Line Items]
Employment Agreement, Severance Terms	50.00%