XML 31 R75.htm IDEA: XBRL DOCUMENT
v3.19.3

Fair Value - Changes in Assets and Liabilities with Inputs Classified within Level 3 of Fair Value (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Sep. 27, 2019 | Sep. 28, 2018 | Sep. 29, 2017
Contingent consideration |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Beginning balance | $ 585 | $ 1,679 | $ 848
Net Realized/Unrealized Losses (Gains) Included in Earnings | 65 | (394) | (180)
Purchases and Issuances | 0 | 0 | 1,701
Sales and Settlements | (650) | (700) | (1,050)
Ending balance | 0 | 585 | 1,679
Warrant liability |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Beginning balance | 13,129 | 40,775 | 38,253
Net Realized/Unrealized Losses (Gains) Included in Earnings | (765) | (27,646) | (2,522)
Purchases and Issuances | 0 | 0 | 0
Sales and Settlements | 0 | 0 | 0
Ending balance | $ 12,364 | $ 13,129 | $ 40,775

X
- Definition Fair value measurement with unobservable inputs reconciliation recurring basis liability purchases and issuances. + References No definition available. + Details
Name: | mtsi_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchasesAndIssuances
Namespace Prefix: | mtsi_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Fair value measurement with unobservable inputs reconciliation recurring basis liability sales and settlement. + References No definition available. + Details
Name: | mtsi_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySalesAndSettlement
Namespace Prefix: | mtsi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=mtsi_ContingentConsiderationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=mtsi_CommonStockWarrantLiabilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |