Note 21 - Subsequent Event	12 Months Ended
Dec. 31, 2020
Notes to Financial Statements
Subsequent Events [Text Block]	21. Subsequent Event On February 1, 2021, we closed on the sale of our Coatings business. We expect to record a gain on the sale in the first quarter of 2021. As of December 31, 2020, this business was considered held for sale, with assets held for sale of $15.0 million and liabilities held for sale of $3.2 million.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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