Note 13 - Accumulated Other Comprehensive Income (Details Textual)	Mar. 31, 2019
Rush Truck Centres of Canada Limited [Member]
Foreign Currency Exchange Rate, Translation	1.3307

Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6897108&loc=SL6897125-166521

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