Note 11 - Business Segments, Sales of Products and Significant Customers - Long-lived Assets by Geographic Area (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Long-lived assets	$ 2,423,698	$ 2,520,004
UNITED STATES
Long-lived assets	1,748,406	1,797,441
CANADA
Long-lived assets	660,859	707,473
MEXICO
Long-lived assets	$ 14,433	$ 15,090

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
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.7-03(a)(8))
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