Note 6 - Stockholders' Equity (Details Textual) $ / shares in Units, $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2022 USD ($) $ / shares shares	Jun. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Sep. 30, 2021 USD ($) $ / shares	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Sep. 30, 2022 USD ($) $ / shares shares	Sep. 30, 2021 USD ($) $ / 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			$ 0.24	$ 0.24
Dividends, Common Stock, Total | $	$ 7	$ 8	$ 8	$ 8	$ 7	$ 8	$ 23	$ 23
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	7,200,000						7,200,000
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
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	2,800,000						2,800,000
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