Note 6 - Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2021
Common Stock, Dividends, Per Share, Declared (in dollars per share)	$ 0.10	$ 10	$ 10
Payments for Repurchase of Common Stock	$ 23			$ 23
Treasury Stock, Shares, Acquired (in shares)	1,000,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 127			$ 127