| Commitments and Contingencies (Details Textual) (USD $) | 1 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Mar. 31, 2012 | Dec. 31, 2014
 lender | Dec. 31, 2013 | Dec. 31, 2012 | Feb. 14, 2014 | Jul. 17, 2013 | Jul. 08, 2013 | Jun. 17, 2013 | Sep. 30, 2012 | Jun. 06, 2011 | Oct. 26, 2011
 JointVenture | |
| Loss Contingencies [Line Items] | |||||||||||
| Reserved for litigation and asserted claims | $ 16,499,000us-gaap_LitigationReserve | $ 16,463,000us-gaap_LitigationReserve | |||||||||
| Warranty reserve | 22,080,000us-gaap_StandardProductWarrantyAccrual | 21,971,000us-gaap_StandardProductWarrantyAccrual | 22,064,000us-gaap_StandardProductWarrantyAccrual | ||||||||
| Number of lenders filing petition for involuntary bankruptcy | 3mth_NumberOfLendersFilingPetitionForInvoluntaryBankruptcy | ||||||||||
| Initial Litigation Judgment Amount | 15,053,857mth_InitialLitigationJudgmentAmount | ||||||||||
| Litigation Judgment Amount With Interest | 15,753,344mth_LitigationJudgmentAmountWithInterest | ||||||||||
| Litigation Judgment Interest | 699,487mth_LitigationJudgmentInterest | ||||||||||
| Supersedeas Bond | 16,930,477mth_SupersedeasBond | 16,050,604mth_SupersedeasBond | |||||||||
| Incremental Attorney Fees to Supersedeas Bond | 877,241mth_IncrementalAttorneyFeestoSupersedeasBond | ||||||||||
| Amount requested in demand for arbitration related to alleged breaches | 13,500,000us-gaap_LossContingencyDamagesSoughtValue | ||||||||||
| Additional amount requested in demand for arbitration related to pro rata future infrastructure improvement costs | 9,800,000mth_FutureInfrastructureImprovementCosts | ||||||||||
| Rent expense | 6,500,000us-gaap_OperatingLeasesRentExpenseNet | 6,400,000us-gaap_OperatingLeasesRentExpenseNet | 5,500,000us-gaap_OperatingLeasesRentExpenseNet | ||||||||
| Sublease income | 600,000us-gaap_OperatingLeasesIncomeStatementSubleaseRevenue | 1,600,000us-gaap_OperatingLeasesIncomeStatementSubleaseRevenue | 2,000,000us-gaap_OperatingLeasesIncomeStatementSubleaseRevenue | ||||||||
| South Edge Guarantee [Member] | |||||||||||
| Loss Contingencies [Line Items] | |||||||||||
| Equity Method Investment, Ownership Percentage | 3.53%us-gaap_EquityMethodInvestmentOwnershipPercentage / us-gaap_GuaranteeObligationsByNatureAxis = mth_SouthEdgeGuaranteeMember | ||||||||||
| Springing Repayment Guarantee Original Demand Letter | $ 13,200,000mth_SpringingRepaymentGuaranteeOriginalDemandLetter / us-gaap_GuaranteeObligationsByNatureAxis = mth_SouthEdgeGuaranteeMember | ||||||||||
| South Edge [Member] | |||||||||||
| Loss Contingencies [Line Items] | |||||||||||
| Number of co-ventures in joint venture | 4mth_NumberOfCoVenturesInJointVenture / us-gaap_LossContingenciesByNatureOfContingencyAxis = mth_SouthEdgeMember | ||||||||||
| X | ||||||||||
| 
- Definition The pro-rata share of alleged future infrastructure improvement costs to be incurred by the joint venture. No definition available. 
 | 
| X | ||||||||||
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- Definition Incremental attorney fees awarded on 2/14/14 related to 7/17/13 supersedeas bond No definition available. 
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| X | ||||||||||
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- Definition Initial litigation judgment amount related to joint venture litigation on June 17, 2013 No definition available. 
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| X | ||||||||||
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- Definition Initial litigation judgment amount related to joint venture litigation on June 17, 2013 including pre-judgment interest on July 8, 2013 No definition available. 
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| X | ||||||||||
| 
- Definition Interest attributable to initial judgment amount related to joint venture litigation ruling on June 17, 2013 No definition available. 
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| X | ||||||||||
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- Definition Number of co ventures in the joint venture. No definition available. 
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| X | ||||||||||
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- Definition The number of lenders who filed a petition seeking to place the venture into an involuntary bankruptcy. No definition available. 
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| X | ||||||||||
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- Definition Amount in original demand letter from lenders seeking to place joint venture into involuntary bankruptcy (June 2011) No definition available. 
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| X | ||||||||||
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- Definition Amount of supersedeas bond posted to stay enforcement of July 17th judgement. No definition available. 
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| X | ||||||||||
| 
- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
| 
- Definition Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Details 
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| X | ||||||||||
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- Definition The value (monetary amount) of the award the plaintiff seeks in the legal matter. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition The amount of revenue recognized for the period under subleasing arrangements. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Details 
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| X | ||||||||||
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- Details 
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