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Contingencies And Commitments [Line Items]

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Initial term of Executive Employment agreement.

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The range of interest rates for all capital leases as of the balance sheet date.

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Loss Contingency, Damages Sought, Value Per Violation

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Number of Former Sales Representatives

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Number of Participants in the Surfactant, Positive Pressure, and Oxygenation Randomized Trial

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Percentage Of Accounts Receivable Balance From Three Just In Time Distributors

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Percentage Of Accounts Receivable Balance From Two Just In Time Distributor

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Percentage of the Company's total revenue that is from one customer.

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Percentage of revenue two customer.

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Sales of products to customers affiliated with Group Purchasing Organizations.

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Royalty revenue earned during the period from a third party resulting from a settlement agreement.

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Royalty rate Percentage.

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Severance plan participation agreements.

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Supplemental Unemployment Benefits, Severance Benefits, Required Notice of Resignation

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for contractual rent under lease arrangements.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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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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 rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

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

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Amount of increase (decrease) in loss contingency liability.

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The total number of new claims filed pertaining to a loss contingency during the period.

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Number of another entity's patents that the entity has allegedly infringed.

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

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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)						1 Months Ended	3 Months Ended			6 Months Ended		12 Months Ended
	Oct. 01, 2014 USD ($)	Jan. 16, 2014 USD ($)	Jan. 03, 2014 USD ($)	Aug. 21, 2013 claim	Jul. 09, 2009 patent	Sep. 30, 2011 sales_representatives	Jul. 04, 2015 USD ($) distributor Agreement	Jun. 28, 2014 USD ($) distributor	Mar. 29, 2014 USD ($)	Jul. 04, 2015 USD ($) distributor Agreement	Jun. 28, 2014 USD ($)	Jan. 03, 2015 USD ($) distributor	Dec. 28, 2013 USD ($)	Jan. 31, 2014 participant
Contingencies And Commitments [Line Items]
Share-based compensation expense							$ 2,535,000	$ 2,608,000		$ 5,429,000	$ 5,208,000
Accrued rent expense							400,000			400,000
Rental expense related to operating leases							1,400,000	1,500,000		$ 2,900,000	3,100,000
Company contribution percentage based on employee contribution of up to 3% of employee's compensation										3.00%
Company's contribution to employee retirement savings plan							$ 600,000	$ 600,000		$ 1,200,000	$ 1,200,000
Initial term of agreement										3 years
Severance plan participation agreements \| Agreement							7			7
Supplemental Unemployment Benefits, Severance Benefits, Required Notice of Resignation										6 months
Purchase Commitment, Remaining Minimum Amount Committed							$ 81,800,000			$ 81,800,000
Bank balances							80,000,000			80,000,000		$ 92,900,000
Bank balance covered by Federal Deposit Insurance Corporation limit							3,300,000			3,300,000
Money Market Funds, at Carrying Value							6,900,000			6,900,000		$ 1,100,000
Money market funds							400,000			400,000
Letters of Credit Outstanding, Amount							$ 1,600,000			$ 1,600,000
Percentage of revenue one customer							15.00%	14.00%		15.00%	14.00%
Percentage of revenue two customer							12.00%	12.00%		12.00%	11.00%
Royalty							$ 8,114,000	$ 7,430,000		$ 15,294,000	$ 15,012,000
Royalty Rate Percentage										7.75%
Number of former sales representatives \| sales_representatives						2
Litigation settlement amount	$ 466,800,000
Increase (decrease) in loss contingency accrual									$ (8,000,000)
Number of participants in the surfactant, positive pressure, and oxygenation randomized trial \| participant														2
Sales
Contingencies And Commitments [Line Items]
Concentration risk, just-in-time distributors \| distributor							2	2		2		3
Minimum
Contingencies And Commitments [Line Items]
Interest rates on capital lease										4.30%
Maximum
Contingencies And Commitments [Line Items]
Interest rates on capital lease										5.20%
Sales Revenue, Product Line [Member]
Contingencies And Commitments [Line Items]
Sale of company's products to customers							$ 84,500,000	$ 78,600,000		$ 170,800,000	$ 153,800,000
Just in time distributor one
Contingencies And Commitments [Line Items]
Percentage Of Accounts Receivable Balance From Three Just In Time Distributors												6.00%
Percentage of accounts receivable balance from two just-in-time distributor										11.00%
Just in time distributor two
Contingencies And Commitments [Line Items]
Percentage Of Accounts Receivable Balance From Three Just In Time Distributors												9.00%
Percentage of accounts receivable balance from two just-in-time distributor										10.00%
Just In Time Distributor Three [Member]
Contingencies And Commitments [Line Items]
Percentage Of Accounts Receivable Balance From Three Just In Time Distributors												5.00%
Masimo vs. Philips
Contingencies And Commitments [Line Items]
Number of patents allegedly infringed \| patent					1
Masimo vs. Mindray DS USA, Inc. and Shenzhen Mindray Bio-Medical Electronics
Contingencies And Commitments [Line Items]
Loss contingency, new claims filed \| claim				2
Masimo vs Former Physician Office Sales Representatives
Contingencies And Commitments [Line Items]
Litigation settlement amount		$ 5,400,000
Litigation settlement expense													$ 2,600,000
Masimo vs. Physicians Healthsource, Inc.
Contingencies And Commitments [Line Items]
Loss contingency, damages sought			$ 500
Parent Company [Member]
Contingencies And Commitments [Line Items]
Number of patents allegedly infringed \| patent					2
Philips Patent [Member]
Contingencies And Commitments [Line Items]
Number of patents allegedly infringed \| patent					1