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Note 10 - Acquisitions (Details) (USD $)	3 Months Ended		0 Months Ended
Note 10 - Acquisitions (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Feb. 09, 2015	Jan. 13, 2014
Note 10 - Acquisitions (Details) [Line Items]
Payments to Acquire Businesses, Gross	$ 27,849,000	$ 143,050,000
Effingham Truck Sales, Inc. [Member] \| Goodwill Acquired [Member]
Note 10 - Acquisitions (Details) [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			15 years
Effingham Truck Sales, Inc. [Member]
Note 10 - Acquisitions (Details) [Line Items]
Payments to Acquire Businesses, Gross			25,300,000
CIT, Inc [Member] \| Goodwill Acquired [Member]
Note 10 - Acquisitions (Details) [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life				15 years
CIT, Inc [Member]
Note 10 - Acquisitions (Details) [Line Items]
Business Combination, Consideration Transferred				146,600,000
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in Shares)				83,091
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned				2,000,000