v3.26.1
Note 4 - Investments and Fair Value Measurements (Tables)
6 Months Ended
Jun. 30, 2026
Notes Tables  
Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block]
   

June 30, 2026

  

December 31, 2025

 
 

Fair Value

 

Carrying

  

Estimated

  

Carrying

  

Estimated

 
 

Hierarchy

 

Value

  

Fair Value

  

Value

  

Fair Value

 

Financial instruments not carried at fair value:

                 

Senior notes (Note 6)

Level 2

 $4,207.6  $4,067.6  $4,715.4  $4,670.6