Note 8 - Goodwill and Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2020

Notes Tables

Schedule of Goodwill [Table Text Block]

	Infrastructure Solutions			Corrosion Protection			Total
Balance, December 31, 2018
Goodwill, gross	$	244,521		$	76,383		$	320,904
Accumulated impairment losses		(62,848	)		(45,400	)		(108,248	)
Goodwill, net		181,673			30,983			212,656
2019 Activity:
Foreign currency translation		(137	)		563			426
Reclassification to assets held for sale (1)		(4,224	)		—			(4,224	)
Balance, December 31, 2019
Goodwill, gross		240,160			76,946			317,106
Accumulated impairment losses		(62,848	)		(45,400	)		(108,248	)
Goodwill, net		177,312			31,546			208,858
2020 Activity:
Foreign currency translation		1,559			248			1,807
Balance, December 31, 2020
Goodwill, gross		241,719			77,194			318,913
Accumulated impairment losses		(62,848	)		(45,400	)		(108,248	)
Goodwill, net	$	178,871		$	31,794		$	210,665

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

	December 31, 2020									December 31, 2019
	Weighted Average Useful Lives (Years)		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
License agreements		—	$	3,894	$	(3,894	)	$	—	$	3,894	$	(3,824	)	$	70
Leases		—		864		(864	)		—		864		(777	)		87
Trademarks		8.4		14,758		(7,459	)		7,299		14,688		(6,695	)		7,993
Non-competes		2.3		1,561		(1,008	)		553		1,556		(784	)		772
Customer relationships		5.7		95,058		(56,602	)		38,456		94,865		(50,104	)		44,761
Patents and acquired technology		6.9		39,756		(27,195	)		12,561		39,288		(25,096	)		14,192
Total intangible assets		—	$	155,891	$	(97,022	)	$	58,869	$	155,155	$	(87,280	)	$	67,875