Note 12 - Business Segments, Sales of Products and Significant Customers - Long-lived Assets by Geographic Area (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Long-lived assets	$ 2,345,219	$ 2,423,698
UNITED STATES
Long-lived assets	1,701,307	1,748,406
CANADA
Long-lived assets	635,788	660,859
MEXICO
Long-lived assets	$ 8,124	$ 14,433

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 944
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