Note 15 - Acquisition of Landair Holdings, Inc - Pro Forma Information (Details) - Landair Holdings Inc [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Total revenue	$ 85,124
Net income	7,418
Total revenue	960,205	$ 825,850
Net income	$ 45,387	$ 56,440
Basic net income per share (in dollars per share)	$ 2.49	$ 3.09
Diluted net income per share (in dollars per share)	$ 2.46	$ 3.07

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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