XML 94 R76.htm IDEA: XBRL DOCUMENT v3.22.4

Benefit Plans, Reconciliation of Changes in Fair Value Measurement of Plan Assets Using Significant Unobservable Inputs (Details) - Significant Unobservable Inputs (Level 3) [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Changes in Fair Value Measurement of Plan Assets [Roll Forward]
Beginning balance	$ 6.0	$ 8.3
Purchases, sales, settlements	0.0	0.0
Actual return on plan assets still held at reporting date	1.8	(2.3)
Foreign exchange impact	(0.2)	0.0
Ending balance	7.6	6.0
Fair Value Transfers [Abstract]
Fair value, assets, Level 3 transfers in, amount	0.0	0.0
Fair value, assets, Level 3 transfers out, amount	$ 0.0	$ 0.0

X

- Definition

Amount of transfers of assets measured on a recurring basis into Level 3.

+ References

No definition available.

+ Details

Name:	mtx_FairValueAssetsLevel3TransfersInAmount
Namespace Prefix:	mtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount of transfers of assets measured on a recurring basis out of Level 3.

+ References

No definition available.

+ Details

Name:	mtx_FairValueAssetsLevel3TransfersOutAmount
Namespace Prefix:	mtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Amount of actual return (loss) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

No definition available.

+ Details

Name:	mtx_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetActualReturnLoss
Namespace Prefix:	mtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of foreign currency translation gain (loss) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

No definition available.

+ Details

Name:	mtx_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetForeignCurrencyTranslationGainLoss
Namespace Prefix:	mtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	mtx_FairValueTransfersAbstract
Namespace Prefix:	mtx_
Data Type:	xbrli:stringItemType
Balance Type:	na
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_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as an asset 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)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

+ Details

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

X

- Definition

Fair value of financial instrument classified as an asset 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 https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

+ Details

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

X

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: