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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

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The net amount of long-lived depreciable assets not included within other defined categories that are subject to a lease meeting the criteria for capitalization.

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No definition available.

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The cumulative amount of depreciation for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization not included within the other defined categories in the taxonomy.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Nominal or face amount used to calculate payments on the derivative asset.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

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Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the rights acquired through a franchise arrangement having an indefinite period of benefit.

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Amount of interest capitalized during the period.

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-Glossary Allowance for Funds Used during Construction

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Represents the number of stores.

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The amount of pension and other (such as medical, dental and life insurance) postretirement benefit costs recognized during the period for (1) defined benefit plans (periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss) on assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments) and for (2) defined contribution plans (to the extent that a plan's defined contributions to an individual's account are to be made for periods in which that individual renders services, the net cost for a period is the contribution called for in that period; if a plan calls for contributions for periods after an individual retires or terminates, the estimated cost is accrued during the employee's service period).

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Note 2 - Significant Accounting Policies (Details) (USD $)	12 Months Ended			1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	May 30, 2013	May 31, 2013
Note 2 - Significant Accounting Policies (Details) [Line Items]
Depreciation	$ 115,300,000us-gaap_Depreciation	$ 82,300,000us-gaap_Depreciation
Amortization	11,200,000us-gaap_AdjustmentForAmortization	11,200,000us-gaap_AdjustmentForAmortization
Capitalized Computer Software, Net	38,500,000us-gaap_CapitalizedComputerSoftwareNet
Capitalized Computer Software, Accumulated Amortization	10,300,000
Finite-Lived Intangible Assets, Amortization Expense, Year Two	3,200,000
Finite-Lived Intangible Assets, Amortization Expense, Year Three	3,200,000
Finite-Lived Intangible Assets, Amortization Expense, Year Four	3,200,000
Finite-Lived Intangible Assets, Amortization Expense, Year Five	3,200,000
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	3,200,000
Indefinite-Lived Franchise Rights	6,900,000us-gaap_IndefiniteLivedFranchiseRights	4,500,000us-gaap_IndefiniteLivedFranchiseRights
Goodwill and Intangible Asset Impairment	0
Advertising Expense	8,700,000us-gaap_AdvertisingExpense	6,800,000us-gaap_AdvertisingExpense	4,400,000us-gaap_AdvertisingExpense
Interest Rate Swap [Member] \| Cash Flow Hedging [Member]
Note 2 - Significant Accounting Policies (Details) [Line Items]
Derivative Asset, Notional Amount	20,900,000
SAP Enterprise Software And SAP Dealership Management System [Member] \| Sales Revenue, Net [Member]
Note 2 - Significant Accounting Policies (Details) [Line Items]
Concentration Risk, Percentage	90.00%
Rush Truck Centers [Member]
Note 2 - Significant Accounting Policies (Details) [Line Items]
Number of Stores	101
Vehicles [Member]
Note 2 - Significant Accounting Policies (Details) [Line Items]
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Other Property, Plant, and Equipment, Net	54,800,000
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Property, Plant, and Equipment Other, Accumulated Depreciation	21,500,000
Computer Software, Intangible Asset [Member]
Note 2 - Significant Accounting Policies (Details) [Line Items]
Interest Costs Capitalized	244,000
Capitalized Computer Software, Net	38,500,000	40,800,000
Capitalized Computer Software, Accumulated Amortization	10,300,000	7,100,000
Finite-Lived Intangible Asset, Useful Life	15 years
Amortization of Intangible Assets	3,200,000	3,000,000	3,000,000
Former Chairman [Member]
Note 2 - Significant Accounting Policies (Details) [Line Items]
Pension and Other Postretirement Benefit Expense				$ 10,800,000	$ 10,800,000