XML 32 R20.htm IDEA: XBRL DOCUMENT
v3.21.1

Revenue Recognition - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020
Disaggregation Of Revenue [Line Items] |  |
Period for credit risk identified | 30 days |
Sales revenues totaling | $ 3.0 |
Lease revenue | 98.0 |
Operating lease revenue | 97.6 |
Finance lease revenue | 0.4 |
Finance lease revenue, sales revenue | 0.3 |
Finance lease revenue, interest income | $ 0.1 |
Period for warranties for rental equipment | 90 days |
Period for warranties for equipment manufactured | 1 year |
Deferred Income [Member] |  |
Disaggregation Of Revenue [Line Items] |  |
Customer contract liability | $ 19.1 | $ 11.3
Accounts Receivable [Member] |  |
Disaggregation Of Revenue [Line Items] |  |
Unbilled contract assets | $ 0.7 | $ 1.4

X
- Definition Products warranty period for equipment manufactured. + References No definition available. + Details
Name: | mgrc_ProductsWarrantyPeriodForEquipmentManufactured
Namespace Prefix: | mgrc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Products warranty period for rental equipment. + References No definition available. + Details
Name: | mgrc_ProductsWarrantyPeriodForRentalEquipment
Namespace Prefix: | mgrc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Revenue credit period for customers. + References No definition available. + Details
Name: | mgrc_RevenueCreditPeriodForCustomers
Namespace Prefix: | mgrc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130531-203044 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130532-203044 + Details
Name: | us-gaap_ContractWithCustomerLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045 + Details
Name: | us-gaap_ContractWithCustomerLiabilityRevenueRecognized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of interest income from net investment in direct financing lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 6A -URI http://asc.fasb.org/extlink&oid=121640914&loc=SL77927221-108306 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 5 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919372-209981 + Details
Name: | us-gaap_DirectFinancingLeaseInterestIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of lease income from variable lease payments, interest income on direct financing lease and after offset of loss recognized at commencement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=121561866&loc=SL77919311-209978 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919372-209981 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 6A -URI http://asc.fasb.org/extlink&oid=121640914&loc=SL77927221-108306 + Details
Name: | us-gaap_DirectFinancingLeaseLeaseIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of direct financing lease revenue. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 5 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919372-209981 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 6A -URI http://asc.fasb.org/extlink&oid=121640914&loc=SL77927221-108306 + Details
Name: | us-gaap_DirectFinancingLeaseRevenue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DisaggregationOfRevenueLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of lease income from operating, direct financing, and sales-type leases. Includes, but is not limited to, variable lease payments, interest income, profit (loss) recognized at commencement, and lease payments paid and payable to lessor. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919372-209981 + Details
Name: | us-gaap_LeaseIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919372-209981 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=121561866&loc=SL77919311-209978 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 6A -URI http://asc.fasb.org/extlink&oid=121640914&loc=SL77927221-108306 + Details
Name: | us-gaap_OperatingLeaseLeaseIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer. + References No definition available. + Details
Name: | us-gaap_UnbilledReceivablesCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=mgrc_DeferredIncomeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=us-gaap_AccountsReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |