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amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 false2Carrying value of debt10false 4us-gaap_InterestExpenseDebtus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse47000004.7falsefalsefalse2truefalsefalse48000004.8falsefalsefalse3truefalsefalse94000009.4falsefalsefalse4truefalsefalse98000009.8falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7truefalsefalse35000003.5falsefalsefalse8truefalsefalse70000007.0falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11truefalsefalse35000003.5falsefalsefalse12truefalsefalse70000007.0falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17truefalsefalse11000001.1falsefalsefalse18truefalsefalse11000001.1falsefalsefalse19truefalsefalse21000002.1falsefalsefalse20truefalsefalse22000002.2falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryRepresents the portion of interest incurred in the period on debt arrangements that was charged against earnings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 8 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 34 -Paragraph 21 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Interest incurred on debt11false 4us-gaap_ExtinguishmentOfDebtAmountus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10truefalsefalse237600000237.6falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryGross amount of debt extinguished.No definition available.false2Principal amount of debt redeemed12false 4mrh_DebtInstrumentRedemptionPriceAsPercentageOfPrincipalAmountmrh_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsetruefalse00falsefalsefalse2falsetruefalse00falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalse5falsetruefalse00falsefalsefalse6falsetruefalse00falsefalsefalse7falsetruefalse00falsefalsefalse8falsetruefalse00falsefalsefalse9falsetruefalse00falsefalsefalse10truetruefalse1.0421.042falsefalsefalse11falsetruefalse00falsefalsefalse12falsetruefalse00falsefalsefalse13falsetruefalse00falsefalsefalse14falsetruefalse00falsefalsefalse15falsetruefalse00falsefalsefalse16falsetruefalse00falsefalsefalse17falsetruefalse00falsefalsefalse18falsetruefalse00falsefalsefalse19falsetruefalse00falsefalsefalse20falsetruefalse00falsefalsefalse21falsetruefalse00falsefalsefalse22falsetruefalse00falsefalsefalse23falsetruefalse00falsefalsefalse24falsetruefalse00falsefalsefalse25falsetruefalse00falsefalsefalse26falsetruefalse00falsefalsefalse27falsetruefalse00falsefalsefalsenum:percentItemTypepureRepresents the redemption price of the debt instrument as a percentage of the principal amount.No definition available.false0Redemption price, as percentage of principal amount of debt instrument13false 4us-gaap_InterestPaidus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8truefalsefalse74000007.4falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11truefalsefalse70000007.0falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19truefalsefalse21000002.1falsefalsefalse20truefalsefalse22000002.2falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of cash paid for interest during the period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 29 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3536-108585 false2Interest paid14false 4us-gaap_DebtInstrumentDescriptionOfVariableRateBasisus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse003-month LIBORfalsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringThe reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.No definition available.false0Floating interest rate, base rate15false 4us-gaap_DebtInstrumentBasisSpreadOnVariableRateus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsetruefalse00falsefalsefalse2falsetruefalse00falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalse5falsetruefalse00falsefalsefalse6falsetruefalse00falsefalsefalse7falsetruefalse00falsefalsefalse8falsetruefalse00falsefalsefalse9falsetruefalse00falsefalsefalse10falsetruefalse00falsefalsefalse11falsetruefalse00falsefalsefalse12falsetruefalse00falsefalsefalse13falsetruefalse00falsefalsefalse14falsetruefalse00falsefalsefalse15falsetruefalse00falsefalsefalse16falsetruefalse00falsefalsefalse17falsetruefalse00falsefalsefalse18falsetruefalse00falsefalsefalse19falsetruefalse00falsefalsefalse20falsetruefalse00falsefalsefalse21truetruefalse0.03800.0380falsefalsefalse22falsetruefalse00falsefalsefalse23falsetruefalse00falsefalsefalse24falsetruefalse00falsefalsefalse25falsetruefalse00falsefalsefalse26falsetruefalse00falsefalsefalse27falsetruefalse00falsefalsefalsenum:percentItemTypepureThe percentage points added to the reference rate to compute the variable rate on the debt instrument.No definition available.false0Floating interest rate, basis points added to base rate (as a percent)16false 4us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMinimumus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsetruefalse00falsefalsefalse2falsetruefalse00falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalse5falsetruefalse00falsefalsefalse6falsetruefalse00falsefalsefalse7falsetruefalse00falsefalsefalse8falsetruefalse00falsefalsefalse9falsetruefalse00falsefalsefalse10falsetruefalse00falsefalsefalse11falsetruefalse00falsefalsefalse12falsetruefalse00falsefalsefalse13falsetruefalse00falsefalsefalse14falsetruefalse00falsefalsefalse15falsetruefalse00falsefalsefalse16falsetruefalse00falsefalsefalse17falsetruefalse00falsefalsefalse18falsetruefalse00falsefalsefalse19truetruefalse0.04070.0407falsefalsefalse20truetruefalse0.04260.0426falsefalsefalse21falsetruefalse00falsefalsefalse22falsetruefalse00falsefalsefalse23falsetruefalse00falsefalsefalse24falsetruefalse00falsefalsefalse25falsetruefalse00falsefalsefalse26falsetruefalse00falsefalsefalse27falsetruefalse00falsefalsefalsenum:percentItemTypepureWhen presenting a range of interest rates, the lowest stated (contractual) rate for funds borrowed under the debt agreement as of the balance sheet date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 false0Floating rate, low end of range (as a percent)17false 4us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMaximumus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsetruefalse00falsefalsefalse2falsetruefalse00falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalse5falsetruefalse00falsefalsefalse6falsetruefalse00falsefalsefalse7falsetruefalse00falsefalsefalse8falsetruefalse00falsefalsefalse9falsetruefalse00falsefalsefalse10falsetruefalse00falsefalsefalse11falsetruefalse00falsefalsefalse12falsetruefalse00falsefalsefalse13falsetruefalse00falsefalsefalse14falsetruefalse00falsefalsefalse15falsetruefalse00falsefalsefalse16falsetruefalse00falsefalsefalse17falsetruefalse00falsefalsefalse18falsetruefalse00falsefalsefalse19truetruefalse0.04110.0411falsefalsefalse20truetruefalse0.04380.0438falsefalsefalse21falsetruefalse00falsefalsefalse22falsetruefalse00falsefalsefalse23falsetruefalse00falsefalsefalse24falsetruefalse00falsefalsefalse25falsetruefalse00falsefalsefalse26falsetruefalse00falsefalsefalse27falsetruefalse00falsefalsefalsenum:percentItemTypepureWhen presenting a range of interest rates, the highest stated (contractual) rate for funds borrowed under the debt agreement as of the balance sheet date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 false0Floating rate, high end of range (as a percent)18false 4mrh_SwapAgreementTermmrh_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse005 yearsfalsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27falsefalsefalse00falsefalsefalsexbrli:durationItemTypenaRepresents the period for which the entity has entered into the swap agreement with a third party.No definition available.false0Swap agreement term19true 4mrh_LetterOfCreditFacilitiesAbstractmrh_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Letter of Credit Facilities20false 5mrh_LineOfCreditFacilityCollateralAmountmrh_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse3210000032.1falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse3210000032.1falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse128000000128.0falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryRepresents the amount of cash and investments provided as collateral for the line of credit facilities.No definition available.false2Cash and investments collateral for letter of credit facilities21false 5us-gaap_LineOfCreditFacilityMaximumBorrowingCapacityus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24truefalsefalse7500000075.0falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27truefalsefalse7500000075.0falsefalsefalsexbrli:monetaryItemTypemonetaryMaximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 false2Total Capacity22false 5us-gaap_LineOfCreditFacilityAmountOutstandingus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24truefalsefalse23000002.3USD$falsetruefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27truefalsefalse2300000023.0USD$falsetruefalsexbrli:monetaryItemTypemonetaryAmount borrowed under the credit facility as of the balance sheet date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 false2Amount Drawn23false 5mrh_DebtInstrumentCovenantTermsLeverageRatioMaximummrh_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsetruefalse00falsefalsefalse2falsetruefalse00falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalse5falsetruefalse00falsefalsefalse6falsetruefalse00falsefalsefalse7falsetruefalse00falsefalsefalse8falsetruefalse00falsefalsefalse9falsetruefalse00falsefalsefalse10falsetruefalse00falsefalsefalse11falsetruefalse00falsefalsefalse12falsetruefalse00falsefalsefalse13falsetruefalse00falsefalsefalse14falsetruefalse00falsefalsefalse15falsetruefalse00falsefalsefalse16falsetruefalse00falsefalsefalse17falsetruefalse00falsefalsefalse18falsetruefalse00falsefalsefalse19falsetruefalse00falsefalsefalse20falsetruefalse00falsefalsefalse21falsetruefalse00falsefalsefalse22falsetruefalse00falsefalsefalse23truetruefalse0.300.30falsefalsefalse24falsetruefalse00falsefalsefalse25falsetruefalse00falsefalsefalse26falsetruefalse00falsefalsefalse27falsetruefalse00falsefalsefalsenum:percentItemTypepureFinancial covenant representing the maximum leverage ratio required to be maintained by the entity.No definition available.false0Debt leverage ratio, maximum (as a percent)24false 5mrh_LineOfCreditFacilityUsedCapacityCommitmentFeePercentagemrh_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsetruefalse00falsefalsefalse2falsetruefalse00falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalse5falsetruefalse00falsefalsefalse6falsetruefalse00falsefalsefalse7falsetruefalse00falsefalsefalse8falsetruefalse00falsefalsefalse9falsetruefalse00falsefalsefalse10falsetruefalse00falsefalsefalse11falsetruefalse00falsefalsefalse12falsetruefalse00falsefalsefalse13falsetruefalse00falsefalsefalse14falsetruefalse00falsefalsefalse15falsetruefalse00falsefalsefalse16falsetruefalse00falsefalsefalse17falsetruefalse00falsefalsefalse18falsetruefalse00falsefalsefalse19falsetruefalse00falsefalsefalse20falsetruefalse00falsefalsefalse21falsetruefalse00falsefalsefalse22falsetruefalse00falsefalsefalse23falsetruefalse00falsefalsefalse24falsetruefalse00falsefalsefalse25truetruefalse0.00250.0025falsefalsefalse26truetruefalse0.00350.0035falsefalsefalse27truetruefalse0.00450.0045falsefalsefalsenum:percentItemTypepureThe fee, expressed as a percentage of the line of credit facility, for used credit capacity under the credit facility.No definition available.false0Annual commitment fee on drawn balances (as a percent)25false 5us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentageus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsetruefalse00falsefalsefalse2falsetruefalse00falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalse5falsetruefalse00falsefalsefalse6falsetruefalse00falsefalsefalse7falsetruefalse00falsefalsefalse8falsetruefalse00falsefalsefalse9falsetruefalse00falsefalsefalse10falsetruefalse00falsefalsefalse11falsetruefalse00falsefalsefalse12falsetruefalse00falsefalsefalse13falsetruefalse00falsefalsefalse14falsetruefalse00falsefalsefalse15falsetruefalse00falsefalsefalse16falsetruefalse00falsefalsefalse17falsetruefalse00falsefalsefalse18falsetruefalse00falsefalsefalse19falsetruefalse00falsefalsefalse20falsetruefalse00falsefalsefalse21falsetruefalse00falsefalsefalse22falsetruefalse00falsefalsefalse23falsetruefalse00falsefalsefalse24truetruefalse0.001250.00125falsefalsefalse25falsetruefalse00falsefalsefalse26falsetruefalse00falsefalsefalse27falsetruefalse00falsefalsefalsenum:percentItemTypepureThe fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.No definition available.false0Annual commitment fee on undrawn balances (as a percent)falseDebt, Letter of Credit Facilities and Trust Arrangements (Details) (USD $)HundredThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.montpelierre.bm/role/DisclosureDebtLetterOfCreditFacilitiesAndTrustArrangementsDetails2725