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Note 3 - Acquisitions - Fair Value of Net Assets Acquired (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Oct. 01, 2020
Goodwill	$ 58,449	$ 58,449
SciSafe Holdings, Inc [Member]
Cash			$ 500
Accounts receivable, net			945
Prepaid expenses and other current assets			31
Property, plant and equipment, net			3,400
Intangible assets			12,100
Intangible assets			12,100
Goodwill			24,943
Other assets			1,547
Accounts payable			(885)
Deferred tax liability			(3,297)
Other liabilities			(2,758)
Fair value of net assets acquired			36,526
SciSafe Holdings, Inc [Member] \| Customer Relationships [Member]
Intangible assets			7,420
Intangible assets			7,420
SciSafe Holdings, Inc [Member] \| Trade Names [Member]
Intangible assets			4,020
Intangible assets			4,020
SciSafe Holdings, Inc [Member] \| Noncompete Agreements [Member]
Intangible assets			660
Intangible assets			$ 660