Depreciation of rental equipment.

No definition available.

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- Definition

Average utilization.

+ References

No definition available.

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- Definition

Rate of utilization is dividing the cost of rental equipment on rent by the total cost of rental equipment excluding accessory equipment. and for Mobile Modular and Adler Tanks excluding new equipment inventory. The Average Utilization for the period is calculated using the average costs of rental equipment.

+ References

No definition available.

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- Definition

Property subject to or available for operating lease acquisition.

+ References

No definition available.

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- Definition

Rental revenues.

+ References

No definition available.

+ Details

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- Definition

Rental related services revenues.

+ References

No definition available.

+ Details

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- Definition

Aggregate revenue during the period from sale of goods and services in the normal course of business, after deducting returns, allowances and discounts.

+ References

No definition available.

+ Details

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- Definition

For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.9)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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 210.7-03.5)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

+ References

+ Details

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- Definition

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The net amount of operating interest income (expense).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.10)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 10

-Article 9

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- Definition

Amount before accumulated depreciation of physical assets used in the normal conduct of business to produce goods and services subject to or available for lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6453916&loc=d3e41457-112716

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-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

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- Definition

The amount of property, by major property class, net of accumulated depreciation, subject to or available for lease as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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Segment Reporting - Summarized Financial Information for Company's Reportable Segments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Rental revenues	$ 71,694mgrc_Rental	$ 69,642mgrc_Rental	$ 65,809mgrc_Rental	$ 62,430mgrc_Rental	$ 66,181mgrc_Rental	$ 65,941mgrc_Rental	$ 63,043mgrc_Rental	$ 60,601mgrc_Rental	$ 269,575mgrc_Rental	$ 255,766mgrc_Rental	$ 248,444mgrc_Rental
Rental related services revenues									64,132mgrc_RentalRelatedServices	53,148mgrc_RentalRelatedServices	46,920mgrc_RentalRelatedServices
Sales and other revenues									74,415mgrc_SalesAndOtherRevenueNet	70,595mgrc_SalesAndOtherRevenueNet	68,675mgrc_SalesAndOtherRevenueNet
Total revenues	111,792us-gaap_Revenues	113,025us-gaap_Revenues	95,745us-gaap_Revenues	87,560us-gaap_Revenues	94,772us-gaap_Revenues	108,839us-gaap_Revenues	87,156us-gaap_Revenues	88,742us-gaap_Revenues	408,122us-gaap_Revenues	379,509us-gaap_Revenues	364,039us-gaap_Revenues
Depreciation of rental equipment									72,678	68,208	63,819
Gross profit	52,204us-gaap_GrossProfit	49,298us-gaap_GrossProfit	42,079us-gaap_GrossProfit	38,638us-gaap_GrossProfit	44,630us-gaap_GrossProfit	45,189us-gaap_GrossProfit	40,169us-gaap_GrossProfit	39,027us-gaap_GrossProfit	182,219us-gaap_GrossProfit	169,015us-gaap_GrossProfit	168,259us-gaap_GrossProfit
Interest expense (income) allocation									9,280us-gaap_InterestIncomeExpenseNet	8,687us-gaap_InterestIncomeExpenseNet	9,149us-gaap_InterestIncomeExpenseNet
Income (loss) before provision for income taxes	24,222	22,609	16,794	12,936	19,341	20,679	16,197	15,157	76,561	71,374	72,867
Rental equipment acquisitions									148,602	136,601	128,754
Accounts receivable, net (period end)	101,294us-gaap_AccountsReceivableNet				87,650us-gaap_AccountsReceivableNet				101,294us-gaap_AccountsReceivableNet	87,650us-gaap_AccountsReceivableNet	92,256us-gaap_AccountsReceivableNet
Rental equipment, at cost (period end)	1,229,638				1,144,168				1,229,638	1,144,168	1,072,845
Rental equipment, net book value (period end)	825,750	817,898	795,532	775,875	767,010	753,810	737,636	726,100	825,750	767,010	718,853
Mobile Modular [Member]
Segment Reporting Information [Line Items]
Rental revenues									96,457	82,503	79,518
Rental related services revenues									35,263	28,891	25,775
Sales and other revenues									29,855	21,267	14,474
Total revenues									161,575	132,661	119,767
Depreciation of rental equipment									16,536	14,459	13,942
Gross profit									63,455	50,423	52,022
Interest expense (income) allocation									4,768	4,318	4,547
Income (loss) before provision for income taxes									16,959	9,617	13,443
Rental equipment acquisitions									82,792	52,953	21,042
Accounts receivable, net (period end)	46,797				37,163				46,797	37,163	39,066
Rental equipment, at cost (period end)	664,340				592,391				664,340	592,391	551,101
Rental equipment, net book value (period end)	473,960				415,366				473,960	415,366	384,813
Utilization (period end)									75.00%	70.70%	66.70%
Average utilization									72.30%	68.30%	66.40%
TRS-RenTelco [Member]
Segment Reporting Information [Line Items]
Rental revenues									99,020	102,101	101,645
Rental related services revenues									3,331	3,095	3,673
Sales and other revenues									25,951	29,857	27,820
Total revenues									128,302	135,053	133,138
Depreciation of rental equipment									40,935	39,953	38,174
Gross profit									60,249	63,520	62,048
Interest expense (income) allocation									2,075	2,156	2,384
Income (loss) before provision for income taxes									34,383	36,633	33,631
Rental equipment acquisitions									45,158	52,625	51,793
Accounts receivable, net (period end)	28,849				27,328				28,849	27,328	24,654
Rental equipment, at cost (period end)	261,995				267,772				261,995	267,772	266,934
Rental equipment, net book value (period end)	105,729				109,988				105,729	109,988	107,999
Utilization (period end)									59.80%	58.20%	64.10%
Average utilization									60.40%	62.70%	65.80%
Adler Tanks [Member]
Segment Reporting Information [Line Items]
Rental revenues									74,098	71,162	67,281
Rental related services revenues									25,538	21,162	17,472
Sales and other revenues									1,152	1,616	2,558
Total revenues									100,788	93,940	87,311
Depreciation of rental equipment									15,207	13,796	11,703
Gross profit									53,452	51,076	51,157
Interest expense (income) allocation									2,618	2,419	2,350
Income (loss) before provision for income taxes									23,605	24,013	26,706
Rental equipment acquisitions									20,652	31,023	55,919
Accounts receivable, net (period end)	21,031				21,915				21,031	21,915	24,323
Rental equipment, at cost (period end)	303,303				284,005				303,303	284,005	254,810
Rental equipment, net book value (period end)	246,061				241,656				246,061	241,656	226,041
Utilization (period end)									63.90%	57.70%	67.50%
Average utilization									62.90%	64.20%	71.50%
Enviroplex [Member]
Segment Reporting Information [Line Items]
Sales and other revenues									17,457	17,855	23,823
Total revenues									17,457	17,855	23,823
Gross profit									5,063	3,996	3,032
Interest expense (income) allocation									(181)	(206)	(132)
Income (loss) before provision for income taxes									1,614	1,111	(913)
Accounts receivable, net (period end)	$ 4,617				$ 1,244				$ 4,617	$ 1,244	$ 4,213