Legal Proceedings (Narrative) (Detail) - Scenario, Plan [Member] - Subsequent Event [Member] - USD ($) $ in Millions	Jul. 27, 2021	Feb. 11, 2021
Maximum [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Amount (Deprecated 2017-01-31)	$ 67.5
Litigation Settlement Amount Awarded From Other Party if Payment Note Made In Full	92.5
Minimum [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Amount (Deprecated 2017-01-31)	$ 55.0	$ 5.0