Note 14 - Capital Stock - Share Repurchase Activity (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
	Oct. 31, 2021	Sep. 30, 2021	Sep. 30, 2021	Aug. 31, 2021	Aug. 14, 2019
3Q19 Repurchase Program
Capital Stock [Line Items]
Stock Repurchase Program, Authorized Amount					$ 200.0
3Q21 Repurchase Program
Capital Stock [Line Items]
Stock Repurchase Program, Authorized Amount				$ 200.0
Total of 3Q19, 1Q20, and 3Q21 Repurchase Programs
Capital Stock [Line Items]
Stock Repurchase Program, Authorized Amount				$ 675.0
Stock Repurchased During Period, Shares		7,100,000	11,400,000
Accelerated Share Repurchases, Final Price Paid Per Share		$ 22.44	$ 22.62
Stock Repurchase Program, Remaining Authorized Repurchase Amount		$ 142.0	$ 142.0
Total of 3Q19, 1Q20, and 3Q21 Repurchase Programs | Subsequent Event
Capital Stock [Line Items]
Stock Repurchased During Period, Shares	2,000,000
Accelerated Share Repurchases, Final Price Paid Per Share	$ 23.72
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 95.5