v3.26.1
Derivatives and Financial Instruments - Recorded Amounts and Estimated Fair Values (Detail) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Derivative [Line Items]    
Total debt $ 1,606.0 $ 1,638.6
Recorded Amount    
Derivative [Line Items]    
Variable rate debt 820.0 852.7
Fixed rate debt 800.0 800.0
Total debt 1,620.0 1,652.7
Fair Value    
Derivative [Line Items]    
Variable rate debt 820.0 852.7
Fixed rate debt 812.4 828.2
Total debt $ 1,632.4 $ 1,680.9