Note 3 - Acquisitions of Ownership Interests (Details Textual) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Equity Method Investments	$ 23,945	$ 23,945	$ 27,821
Syapse, Inc. [Member]
Proceeds from Issuance of Preferred Stock and Preference Stock		68,000
Aktana, Inc. [Member]
Convertible Bridge Loan	1,700
Equity Method Investments	$ 14,200	$ 14,200
Equity Method Investment, Ownership Percentage	15.00%	15.00%
Syapse, Inc. [Member]
Equity Method Investment, Dilution Gain		$ 7,300
Equity Method Investment, Ownership Percentage	11.10%	11.10%
Trice Medical [Member]
Convertible Bridge Loan		$ 1,000
Equity Method Investments	$ 10,800	$ 10,800
Equity Method Investment, Dilution Gain	$ 2,000
Equity Method Investment, Ownership Percentage	12.60%	12.60%

The amount of funding for convertible bridge loans in the period.

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- Definition

Amount of gain related to the equity issuance of equity method investee.

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
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-Paragraph 3
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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8813-108599

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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- Definition

Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholders and which takes precedence over common stockholders in the event of liquidation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585

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