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Pensions and Other Post-Employment Benefits (Details Textual) (USD $)
 3 Months Ended 12 Months Ended
Mar. 28, 2014
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Pension and other post-retirement benefits (Textual) [Abstract]        
Expected rate of return assumption   7.25%mtrn_ExpectedRateOfReturnAssumption 7.50%mtrn_ExpectedRateOfReturnAssumption 7.75%mtrn_ExpectedRateOfReturnAssumption
Domestic expected long-term rate of return assumption   7.25%mtrn_DomesticExpectedLongTermRateOfReturnAssumption    
Increase graded assumption for the domestic rate of compensation   4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease    
Maturity Of debt securities five years or less      
Mutual fund that typically invests at least of its assets in equity and debt securities 80.00%mtrn_InvestmentsInRealEstateMinimumPercentage      
Period of written notice for withdrawals from multi-strategy hedge fund partnerships   10 days    
Percentage of withdrawals of the capital accounts   100.00%mtrn_MaximumPercentageOfWithdrawalsOfCapitalAccountsOfWhichAtLeastThirtyDaysNoticeIsRequired    
Target funded status percentage   100.00%mtrn_TargetFundedStatusPercentage    
Current asset allocation to invest in alternative securities, maximum   20.00%mtrn_CurrentAssetAllocationToInvestInAlternativeSecuritiesMaximum    
Domestic defined benefit pension plan   $ 16,000,000mtrn_DomesticDefinedBenefitPlanEstimatedFutureEmployerContributionsInNextFiscalYear    
Other defined benefit plan estimated future employer contributions in next fiscal year   1,500,000mtrn_OtherDefinedBenefitPlanEstimatedFutureEmployerContributionsInNextFiscalYear    
Liability for other post-employment arrangements   103,891,000us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent 80,275,000us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent  
Company's annual contributions   3,000,000us-gaap_DefinedContributionPlanCostRecognized 2,800,000us-gaap_DefinedContributionPlanCostRecognized 2,500,000us-gaap_DefinedContributionPlanCostRecognized
Foreign Pension Plans Defined Benefit [Member]        
Pension and other post-retirement benefits (Textual) [Abstract]        
Liability for other post-employment arrangements   2,100,000us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember		 2,300,000us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember		  
Pension Plan [Member]        
Pension and other post-retirement benefits (Textual) [Abstract]        
Change in plan liability $ 14,000,000us-gaap_DefinedBenefitPlanBenefitObligationPeriodIncreaseDecrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember		      
Minimum [Member]        
Pension and other post-retirement benefits (Textual) [Abstract]        
Minimum period of written notice for other withdrawals   3 months    
Maximum [Member]        
Pension and other post-retirement benefits (Textual) [Abstract]        
Maturity of foreign debt securities   5 years    
Equity Securities [Member]        
Pension and other post-retirement benefits (Textual) [Abstract]        
Current asset allocation to invest in equity securities, minimum   30.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMinimum
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquitySecuritiesMember		    
Current asset allocation to invest in equity securities, maximum   70.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMaximum
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquitySecuritiesMember		    
Fixed Income Funds [Member]        
Pension and other post-retirement benefits (Textual) [Abstract]        
Current asset allocation to invest in equity securities, minimum   20.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMinimum
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_FixedIncomeFundsMember		    
Current asset allocation to invest in equity securities, maximum   50.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMaximum
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_FixedIncomeFundsMember		    
England [Member] | Foreign Pension Plans Defined Benefit [Member]        
Pension and other post-retirement benefits (Textual) [Abstract]        
Percent of Company aggregated total fair value of plan assets   4.00%mtrn_DefinedBenefitPlanPercentOfCompanyAggregatedTotalFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementGeographicalAxis
= country_GB