Note 7 - Subsequent Event (Details Textual) - Subsequent Event [Member] - USD ($) $ / shares in Units, $ in Millions	Dec. 02, 2020	Nov. 24, 2020
Common Stock, Dividends, Per Share, Declared (in dollars per share)	$ 6.00	$ 3.00
Dividends, Cash, Total	$ 280
Dividends Payable, Date Declared		Nov. 24, 2020
Dividends Payable, Date of Record		Dec. 04, 2020
Dividends Payable, Date to be Paid		Feb. 02, 2021

Aggregate dividends declared during the period for each share of common stock outstanding.

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Date the declared dividend will be paid, in CCYY-MM-DD format.

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Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

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