Refers to the settlement amount received from US government against consent decree.

No definition available.

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- Definition

Low-end of the range estimate of the cost of wastewater treatment facilities upgrade at the entity's Adams, Massachusetts plant.

+ References

No definition available.

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- Definition

High-end of the range estimate of the cost of wastewater treatment facilities upgrade at the entity's Adams, Massachusetts plant.

+ References

No definition available.

+ Details

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- Definition

Refers to minimum number of cases settle during the period.

+ References

No definition available.

+ Details

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- Definition

Number of contracts entered with Armada during the period.

+ References

No definition available.

+ Details

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- Definition

Number of ship loads of bauxite from India to China.

+ References

No definition available.

+ Details

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 7

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-Topic 450

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-SubTopic 20

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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- Definition

Number of claims dismissed.

+ References

No definition available.

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- Definition

Amount of damages awarded to the plaintiff in the legal matter.

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-SubTopic 20

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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- Definition

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

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-Name Accounting Standards Codification

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-SubTopic 20

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- Definition

Number of pending claims pertaining to a loss contingency.

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Name of the individual site or other grouping of the contingency.

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Contingencies (Details) In Millions, unless otherwise specified	3 Months Ended			3 Months Ended				3 Months Ended
	Mar. 29, 2015 USD ($) Load Contract	Mar. 29, 2015 BRL	Oct. 24, 2014 USD ($)	Mar. 29, 2015 Administrative Consent Order For Contamination Associated with Historic Use of PCBs [Member] USD ($)	Mar. 29, 2015 Administrative Consent Order For Installation of Groundwater Contamination System [Member] USD ($)	Mar. 29, 2015 AMCOL International Corporation [Member]	Dec. 31, 2009 AMCOL International Corporation [Member]	Mar. 29, 2015 Silica Cases [Member] Cases	Mar. 29, 2015 Silica Cases [Member] AMCOL International Corporation [Member] Cases	Mar. 29, 2015 Asbestos Cases [Member] Cases	Mar. 29, 2015 Asbestos Cases [Member] AMCOL International Corporation [Member] Cases
Loss Contingencies [Line Items]
Ownership interest (in hundredths)						19.00%	20.00%
Number of contracts entered	2mtx_NumberOfContractsEntered	2mtx_NumberOfContractsEntered
Number of ship loads	60mtx_NumberOfShipLoads	60mtx_NumberOfShipLoads
Default arbitration award	$ 70
Damages sought		34
Number of pending cases								77	5	13
Number of cases dismissed to date								1,419	25	42	1
Number of new cases filed during the quarter								0		3
Number of cases settle								1		0
Site Contingency [Line Items]
Location of plant				Canaan, Connecticut	Adams, Massachusetts plant
Consent decree paid by US government			2.3mtx_ConsentDecreeSettlement
Estimated accrued remediation cost				0.4	0.4
Estimated cost of wastewater treatment upgrades, lower range					6
Estimated cost of wastewater treatment upgrades, upper range					$ 8