Condensed Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Revenues
Rental	$ 65,502mgrc_Rental	$ 62,430mgrc_Rental
Rental related services	15,367mgrc_RentalRelatedServices	13,512mgrc_RentalRelatedServices
Rental operations	80,869	75,942
Sales	8,787us-gaap_SalesRevenueNet	11,038us-gaap_SalesRevenueNet
Other	532us-gaap_OtherSalesRevenueNet	580us-gaap_OtherSalesRevenueNet
Total revenues	90,188us-gaap_Revenues	87,560us-gaap_Revenues
Direct costs of rental operations:
Depreciation of rental equipment	18,682	17,897
Rental related services	11,899mgrc_CostOfRentalRelatedServices	10,307mgrc_CostOfRentalRelatedServices
Other	15,211us-gaap_OtherCostOfOperatingRevenue	13,550us-gaap_OtherCostOfOperatingRevenue
Total direct costs of rental operations	45,792	41,754
Costs of sales	5,309	7,168
Total costs of revenues	51,101us-gaap_CostOfRevenue	48,922us-gaap_CostOfRevenue
Gross profit	39,087us-gaap_GrossProfit	38,638us-gaap_GrossProfit
Selling and administrative expenses	25,212	23,411
Income from operations	13,875us-gaap_OperatingIncomeLoss	15,227us-gaap_OperatingIncomeLoss
Other income (expense):
Interest expense	(2,391)us-gaap_InterestExpenseDebt	(2,203)us-gaap_InterestExpenseDebt
Foreign currency exchange loss	(168)	(88)
Income before provision for income taxes	11,316	12,936
Provision for income taxes	4,470us-gaap_IncomeTaxExpenseBenefit	5,065us-gaap_IncomeTaxExpenseBenefit
Net income	$ 6,846us-gaap_NetIncomeLoss	$ 7,871us-gaap_NetIncomeLoss
Earnings per share:
Basic	$ 0.26us-gaap_EarningsPerShareBasic	$ 0.31us-gaap_EarningsPerShareBasic
Diluted	$ 0.26us-gaap_EarningsPerShareDiluted	$ 0.30us-gaap_EarningsPerShareDiluted
Shares used in per share calculation:
Basic	26,091	25,789
Diluted	26,276	26,230
Cash dividends declared per share	$ 0.250	$ 0.245

Costs of sale of leased property and equipment.

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