Fair Value Measurements (Summary Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Detail) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Derivative, notional amount	$ 94.0	$ 3.0
Derivative asset	1.6	0.0
Derivative liability	0.0	0.1
Other assets, fair value disclosure	0.6	1.6
Long-term debt, fair value	$ 881.2	$ 984.9