Note 11 - Equity Method Investment (Details Textual) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Proceeds from Sale of Property, Plant, and Equipment, Total			$ 86,555	$ 31,235
Reversal of Deferred Gains of Sale of Property			(77)	(7)
Income (Loss) from Equity Method Investments, Total	$ 1,176	$ 2,138	971	7,548
Transport Enterprise Leasing LLC [Member]
Proceeds from Sale of Property, Plant, and Equipment, Total			0	0
Revenue from Related Parties			6,300	7,100
Reversal of Deferred Gains of Sale of Property			$ 100	$ 100
Equity Method Investment, Ownership Percentage	49.00%	49.00%	49.00%	49.00%
Due from Related Parties, Total	$ 800		$ 800		$ 1,200
Income (Loss) from Equity Method Investments, Total			1,000
Proceeds from Equity Method Investment, Distribution		$ 1,200	0	$ 1,200
Equity Method Investments	33,000		33,000		$ 32,400
Transport Enterprise Leasing LLC [Member] \| Reduction in TEL Investment [Member]
Deferred Gain on Sale of Property	$ 100	$ 200	$ 100	$ 200

Amounts reversed from the deferred gains on sale of property.

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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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