Quarterly report pursuant to Section 13 or 15(d)

Loans Payable and Other Borrowings Details Textual (Details)

v2.4.1.9
Loans Payable and Other Borrowings Details Textual (Details) (USD $)
3 Months Ended
Mar. 31, 2015
Dec. 31, 2014
Jul. 31, 2012
Line of Credit Facility [Line Items]      
Proceeds from Long-term Lines of Credit $ 100,000,000us-gaap_LineOfCreditFacilityMaximumAmountOutstandingDuringPeriod    
Letters of Credit Outstanding, Amount 19,712,000us-gaap_LettersOfCreditOutstandingAmount 19,489,000us-gaap_LettersOfCreditOutstandingAmount  
Line of Credit Facility, Remaining Borrowing Capacity 453,300,000us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity    
Notes Payable, Other Payables [Member]      
Line of Credit Facility [Line Items]      
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum 0.00%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMinimum
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_NotesPayableOtherPayablesMember
   
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum 6.00%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMaximum
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_NotesPayableOtherPayablesMember
   
Long-term Debt 34,406,000us-gaap_LongTermDebt
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_NotesPayableOtherPayablesMember
[1] 30,722,000us-gaap_LongTermDebt
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_NotesPayableOtherPayablesMember
[1]  
Letter of Credit [Member]      
Line of Credit Facility [Line Items]      
Line of Credit Facility, Maximum Borrowing Capacity   200,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= us-gaap_LetterOfCreditMember
 
Revolving Credit Facility [Member]      
Line of Credit Facility [Line Items]      
Line of Credit Facility, Maximum Borrowing Capacity 500,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
400,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
125,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
Minimum Tangible Net Worth 670,300,000mth_MinimumTangibleNetWorth
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
   
Leverage ratio (as a percentage) 60.00%mth_LeverageRatio
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
   
Interest Coverage Ratio 1.5mth_InterestCoverageRatio
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
   
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member]      
Line of Credit Facility [Line Items]      
Debt Instrument, Description of Variable Rate Basis LIBOR    
Debt Instrument, Base Rate 0.18%mth_DebtInstrumentBaseRate
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_VariableRateAxis
= us-gaap_LondonInterbankOfferedRateLIBORMember
   
Debt Instrument, Basis Spread on Variable Rate 2.25%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_VariableRateAxis
= us-gaap_LondonInterbankOfferedRateLIBORMember
   
Revolving Credit Facility [Member] | Prime Rate [Member]      
Line of Credit Facility [Line Items]      
Debt Instrument, Description of Variable Rate Basis Prime    
Debt Instrument, Base Rate 3.25%mth_DebtInstrumentBaseRate
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_VariableRateAxis
= us-gaap_PrimeRateMember
   
Debt Instrument, Basis Spread on Variable Rate 1.25%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_VariableRateAxis
= us-gaap_PrimeRateMember
   
Revolving Credit Facility [Member] | Line of Credit [Member]      
Line of Credit Facility [Line Items]      
Long-term Debt $ 27,000,000us-gaap_LongTermDebt
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_LineOfCreditMember
$ 0us-gaap_LongTermDebt
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_LineOfCreditMember
 
[1] Reflects balance of non-recourse notes payable in connection with land purchases, with interest rates ranging from 0% to 6%.