Share-Based Compensation Arrangement By Share-Based Payment Award, Change In Control, Immediate Award Vesting Period

No definition available.

Name:	matv_ShareBasedCompensationArrangementByShareBasedPaymentAwardChangeInControlImmediateAwardVestingPeriod
Namespace Prefix:	matv_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other than Options, Converted At Acquisition, Fair Value

+ References

No definition available.

+ Details

Name:	matv_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtAcquisitionFairValue
Namespace Prefix:	matv_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Converted At Acquisition, Number

+ References

No definition available.

+ Details

Name:	matv_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtAcquisitionNumber
Namespace Prefix:	matv_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

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

- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

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

- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

+ References

No definition available.

+ Details

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

- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AwardTypeAxis=matv_RestrictedStockServiceSharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=matv_A2015LongTermIncentivePlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=matv_RestrictedStockPerformanceSharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=matv_NeenahIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=matv_PerformanceShareUnitsPSUsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Equity-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
Equity-Based Compensation (Details) - USD ($) $ in Millions	Sep. 30, 2022	Sep. 30, 2022	Dec. 31, 2015	Mar. 28, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock compensation expense	$ 1.9	$ 1.9
Restricted Stock Plan Service Based Shares \| CIC event \| LTIP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Immediate vesting period			24 months
Accelerated service awards expensed	2.1
Restricted Stock Plan Performance Based Shares \| LTIP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Accelerated service awards expensed	2.5	2.5
Costs to be recognized	0.6	0.6
Stock compensation expense	$ 2.5	$ 2.5
Restricted Stock Plan Performance Based Shares \| CIC event \| LTIP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting percent		100.00%
RSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting percent		33.30%
RSUs issued as retirement and special grant awards		3 years
RSUs \| Retirement and special grant awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
RSUs issued as retirement and special grant awards		1 year
RSUs \| Neenah
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Assumed unvested shares converted (in shares)				180,149
Assumed unvested shares converted				$ 4.2
PSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Service condition		3 years
Weighted-average period for recognition		2 years
PSUs \| Neenah
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Assumed unvested shares converted (in shares)				292,032
Assumed unvested shares converted				$ 6.8