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 investment in equity security without readily determinable fair value.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

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The percent ownership of equity securities without readily determinable fair value.

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The amount of provision for credit loss on investments.

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Note 4 - Fair Value Measurements (Details Textual) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Feb. 01, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	May 25, 2021	Dec. 31, 2020
Payments to Acquire Investments, Total		$ 6,000	$ (0)	$ 21,100	$ 63,800
Investment in Limited Partnership Member]
Equity Method Investments		51,800		51,800			$ 49,500
Provision for Credit Loss on Investments		0		0
Cost Based Investments [Member]
Investments, Total		161,600		161,600			143,100
Vexcel Group, Inc. [Member]
Payments to Acquire Investments, Total	$ 63,800
Equity Securities Without Readily Determinable Fair Value, Percentage	35.00%					3.70%
Equity Securities without Readily Determinable Fair Value, Amount		144,100		144,100		$ 15,000	129,100
Registered Investment Companies [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Investments, Fair Value Disclosure, Total		$ 4,600		$ 4,600			$ 4,100