Note 9 - Financial Instruments and Fair Value - Pre-tax Effect of Interest Rate Swaps (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Long-lived assets held for sale, fair value	$ 9,505
Long-lived assets held for sale, gain (loss) included in earnings		$ (7,481)

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

No definition available.

Name:	rusha_FairValueMeasurementWithUnobservableInputsReconciliationNonrecurringBasisAssetGainLossIncludedInEarnings
Namespace Prefix:	rusha_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration