Note 9 - Equity Method Investment (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Proceeds from Sale of Property, Plant, and Equipment, Total	$ 18,497	$ 4,431
Reversal of Deferred Gains of Sale of Property	(2)	(1)
Income (Loss) from Equity Method Investments, Total	(735)	3,035
Transport Enterprise Leasing LLC [Member]
Proceeds from Sale of Property, Plant, and Equipment, Total	0	0
Revenue from Related Parties	2,300	2,400
Reversal of Deferred Gains of Sale of Property	$ 100
Equity Method Investment, Ownership Percentage	49.00%
Due from Related Parties, Total	$ 1,400		$ 1,300
Income (Loss) from Equity Method Investments, Total	700
Proceeds from Equity Method Investment, Distribution		$ 0
Equity Method Investments	31,200		$ 31,900
Transport Enterprise Leasing LLC [Member] \| Reduction in TEL Investment [Member]
Deferred Gain on Sale of Property	$ 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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