Note 7 - Goodwill and Intangible Assets (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020		Jun. 30, 2019
Goodwill, Impairment Loss	$ 1,258	$ 0	$ 1,258	[1]	$ 0
Impairment of Intangible Assets, Finite-lived	957	0	957		0
Amortization of Intangible Assets, Total	3,400	$ 3,400	6,800		$ 6,900
Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year	13,000		13,000
Finite-Lived Intangible Asset, Expected Amortization, Year Two	12,900		12,900
Finite-Lived Intangible Asset, Expected Amortization, Year Three	12,900		12,900
Finite-Lived Intangible Asset, Expected Amortization, Year Four	12,900		12,900
Finite-Lived Intangible Asset, Expected Amortization, Year Five	12,100		12,100
Energy Services [Member]
Goodwill, Impairment Loss	1,300		1,258	[1]
Impairment of Intangible Assets, Finite-lived			$ 1,000
Energy Services [Member] | Trademarks [Member]
Impairment of Intangible Assets, Finite-lived	300
Energy Services [Member] | Customer Relationships [Member]
Impairment of Intangible Assets, Finite-lived	$ 700

[1] During the second quarter of 2020, the Company recorded a $1.3 million goodwill impairment related to restructuring activities in Energy Services (see Note 4).