Note 5 - Equity Method Investment (Details Textual) - USD ($) $ in Thousands		12 Months Ended
Sep. 02, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Payments to Acquire Equity Method Investments		$ 27,894	$ (0)	$ (0)
Equity Method Investments		27,894	$ 0
Income (Loss) from Equity Method Investments, Total		$ 0
Privately Held Company [Member]
Equity Method Investment, Ownership Percentage	19.00%
Payments to Acquire Equity Method Investments	$ 27,900
Equity Method Investments	26,600
Equity Method Investment, Aggregate Cost	$ 1,300

This element represents the aggregate cost of investments accounted for under the equity method of accounting.

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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.

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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.

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- Definition

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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