Note 6 - Stockholders' Equity (Details Textual) $ / shares in Units, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2022 USD ($) $ / shares shares	Mar. 31, 2022 USD ($)	Jun. 30, 2021 USD ($) $ / shares	Mar. 31, 2021 USD ($)	Jun. 30, 2022 USD ($) $ / shares shares	Jun. 30, 2021 $ / shares	May 05, 2022 shares	Dec. 31, 2021 shares
Capital Units, Authorized (in shares)	245,000,000				245,000,000
Common Stock, Shares Authorized (in shares)	200,000,000				200,000,000
Preferred Stock, Shares Authorized (in shares)	20,000,000				20,000,000
Common Stock, Voting Rights, Votes Per Share	1				1
Common Stock, Dividends, Per Share, Declared (in dollars per share) | $ / shares	$ 0.08		$ 0.08		$ 0.16	$ 0.16
Dividends, Common Stock, Total | $	$ 8	$ 8	$ 7	$ 8	$ 15
Number of Additional Shares Authorized (in shares)							5,500,000
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	7,500,000				7,500,000			2,800,000
Treasury Stock, Value, Acquired, Cost Method | $	$ 50
Class A Common Stock (No Par Value) [Member]
Common Stock, Shares Authorized (in shares)	25,000,000				25,000,000			25,000,000
Common Stock, Voting Rights, Votes Per Share	10				10
Number of Additional Shares Authorized (in shares)							2,200,000
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	2,800,000				2,800,000			800,000
Common Stock and Class A Common Stock [Member]
Stock Repurchased During Period, Shares (in shares)					2,600,000
Treasury Stock, Value, Acquired, Cost Method | $					$ 50
Stock Repurchase Program, Authorized Amount | $	$ 124				$ 124