Note 10 - Income Taxes - Reconciliation of Income Tax Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statutory federal rate applied to income before income tax expense	$ (17)	$ 129	$ 35
Current year permanent items	11	5	33
State and local taxes, net of federal tax benefit	(4)	26	10
Change in valuation allowance	(1)	0	0
Other items, net	5	(1)	0
Income tax (benefit) expense as recorded	$ (6)	$ 159	$ 78
Effective income tax rate	7.00%	26.00%	46.00%