Note 12 - Segment Reporting - Long-lived Assets by Geographic Region (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Long-lived assets	$ 234,211	$ 228,001
Operating Segments [Member] \| United States Segment [Member]
Long-lived assets	191,296	185,979
Operating Segments [Member] \| Europe Segment [Member]
Long-lived assets	35,465	34,577
Operating Segments [Member] \| Japan Segment [Member]
Long-lived assets	$ 7,450	$ 7,445

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
-Publisher FASB
-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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