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v2.4.1.9

Notes Payable - Components of Notes Payable (Parenthetical) (Detail) (Senior Notes [Member]) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2014 | Apr. 21, 2011 | Mar. 17, 2014
4.03% senior notes due in 2018 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Senior Notes, interest rate | 4.03%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = mgrc_FourPointZeroThreePercentDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember | 4.03%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = mgrc_FourPointZeroThreePercentDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |
Senior Notes, year of maturity | 2018 |  |
3.68% senior notes due in 2021 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Senior Notes, interest rate | 3.68%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = mgrc_ThreePointSixEightPercentDueTwoThousandTwentyOneMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  | 3.68%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = mgrc_ThreePointSixEightPercentDueTwoThousandTwentyOneMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember
Senior Notes, year of maturity | 2021 |  |

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References 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 + Details
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- Details
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