Note 10 - Leases - Lease Expense (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Lease, Cost [Abstract]
Amortization of leased assets		$ 1	$ 1	$ 1
Interest on lease liabilities		0	0	0
Operating lease expense		16	16	17
Variable lease expense (1)	[1]	7	7	7
Total lease expense		$ 24	$ 24	$ 25

[1] Variable lease expense is related to real estate leases and primarily includes taxes, insurance and operating costs.