Note 8 - Goodwill and Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2019

Notes Tables

Schedule of Goodwill [Table Text Block]

	Infrastructure Solutions			Corrosion Protection			Energy Services			Total
Balance, December 31, 2017
Goodwill, gross	$	246,486		$	74,369		$	80,246		$	401,101
Accumulated impairment losses		(61,459	)		(45,400	)		(33,527	)		(140,386	)
Goodwill, net		185,027			28,969			46,719			260,715
2018 Activity:
Acqusitions (1)		—			2,715			1,258			3,973
Impairments (2)		(1,389	)		—			—			(1,389	)
Foreign currency translation		(1,965	)		(701	)		—			(2,666	)
Balance, December 31, 2018
Goodwill, gross	$	244,521		$	76,383		$	81,504		$	402,408
Accumulated impairment losses		(62,848	)		(45,400	)		(33,527	)		(141,775	)
Goodwill, net		181,673			30,983			47,977			260,633
2019 Activity:
Foreign currency translation		(137	)		563			—			426
Reclassification to assets held for sale (3)		(4,224	)		—			—			(4,224	)
Balance, December 31, 2019
Goodwill, gross		240,160			76,946			81,504			398,610
Accumulated impairment losses		(62,848	)		(45,400	)		(33,527	)		(141,775	)
Goodwill, net	$	177,312		$	31,546		$	47,977		$	256,835

Schedule of Finite-Lived Intangible Assets [Table Text Block]

	December 31, 2019									December 31, 2018
	Weighted Average Useful Lives (Years)		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
License agreements		0.7	$	3,894	$	(3,825	)	$	70	$	3,894	$	(3,716	)	$	178
Leases		1.0		864		(777	)		87		864		(689	)		175
Trademarks		8.3		15,699		(6,911	)		8,788		15,751		(6,202	)		9,549
Non-competes		3.3		2,301		(1,354	)		947		2,529		(1,229	)		1,300
Customer relationships		7.2		157,576		(76,832	)		80,744		159,719		(66,753	)		92,966
Patents and acquired technology		9.0		39,288		(25,097	)		14,192		38,338		(22,810	)		15,528
Total intangible assets		—	$	219,622	$	(114,795	)	$	104,828	$	221,095	$	(101,399	)	$	119,696