Net receivable or payable balance eliminated upon consolidation.

No definition available.

Name:	masi_AccountsReceivablesPayablesEliminatedUponConsolidation
Namespace Prefix:	masi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The adjusted minimum annual aggregate royalty expense for all licensed parameters, under certain circumstances.

+ References

No definition available.

+ Details

Name:	masi_AdjustedRoyaltiesPayableLicensed
Namespace Prefix:	masi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The adjusted minimum annual aggregate royalty expense for non-licensed parameters, under certain circumstances.

+ References

No definition available.

+ Details

Name:	masi_AdjustedRoyaltiesPayableNonLicensed
Namespace Prefix:	masi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Deferred revenue eliminated upon consolidation.

+ References

No definition available.

+ Details

Name:	masi_DeferredRevenueEliminatedUponConsolidation
Namespace Prefix:	masi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The percentage rate used to determine the amount of expense related to royalty payments under a contractual arrangement such as payment for use of technology or intellectual property.

+ References

No definition available.

+ Details

Name:	masi_PercentageOfRoyaltyExpense
Namespace Prefix:	masi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of certain expenses that are reimbursed to the Variable Interest Entity.

+ References

No definition available.

+ Details

Name:	masi_PercentageReimbursed
Namespace Prefix:	masi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Variable interest entity consolidated carrying amount intangible assets.

+ References

No definition available.

+ Details

Name:	masi_VariableInterestEntityConsolidatedCarryingAmountIntangibleAssets
Namespace Prefix:	masi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Variable interest entity consolidated carrying amount property and equipment.

+ References

No definition available.

+ Details

Name:	masi_VariableInterestEntityConsolidatedCarryingAmountPropertyAndEquipment
Namespace Prefix:	masi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.31)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 27

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 20

-Article 7

+ Details

Name:	us-gaap_MinorityInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of cash paid for royalties during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

+ Details

Name:	us-gaap_PaymentsForRoyalties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of costs incurred under a research and development arrangement accounted for as a contract to perform research and development for others.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 730

-SubTopic 20

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23221-108380

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 730

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23199-108380

+ Details

Name:	us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersCostsIncurredGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (bb)

-URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5710-111685

+ Details

Name:	us-gaap_VariableInterestEntityConsolidatedCarryingAmountAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

+ References

+ Details

Name:	us-gaap_VariableInterestEntityConsolidatedCarryingAmountLiabilities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_VariableInterestEntityLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=us-gaap_VariableInterestEntityPrimaryBeneficiaryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ProductOrServiceAxis=masi_HandheldProductsIncorporatingRainbowTechnologyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ProductOrServiceAxis=masi_LicensedRainbowParametersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=us-gaap_VariableInterestEntityPrimaryBeneficiaryMember
Namespace Prefix:
Data Type:	na
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Variable Interest Entity (VIE) - Additional Information (Detail) (USD $)	3 Months Ended	1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 04, 2015	Feb. 28, 2009	Mar. 29, 2014	Sep. 28, 2013	Dec. 31, 2011	Jan. 03, 2015
Variable Interest Entity [Line Items]
Noncontrolling interest	1,045,000us-gaap_MinorityInterest					$ 1,742,000us-gaap_MinorityInterest
Licensed rainbow parameters
Variable Interest Entity [Line Items]
Percentage of royalty expense	10.00%
Handheld Products Incorporating Rainbow Technology
Variable Interest Entity [Line Items]
Percentage of royalty expense	10.00%
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Minimum aggregate royalty payments	1,300,000		1,500,000
Increase in royalties payable in current year	15,000,000.0
Increase in the minimum aggregate annual royalties payment	2,000,000.0
Percentage reimbursed	60.00%	50.00%
Total expenses for additional services, materials and supplies	100,000			900,000
Deferred revenue related to technology eliminated upon consolidation	6,400,000					6,500,000
Accounts receivable (payable) eliminated upon consolidation, net						2,000,000
Noncontrolling interest	1,000,000					1,700,000
Total assets, net of intercompany eliminations	6,500,000					7,200,000
Intangible assets	4,800,000					4,700,000
Property and equipment	1,000,000					1,200,000
Total liabilities, net of intercompany eliminations	1,500,000					1,200,000
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Percentage reimbursed					50.00%
Minimum \| Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Minimum aggregate royalty payments	5,000,000.0