Fair Value Measurements (Summary Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Detail) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Derivative, Notional Amount	$ 42.5	$ 56.6
Derivative Asset	0.1	0.1
Derivative Liability	0.1	0.1
Other Assets, Fair Value Disclosure	1.3	1.4
Long-term Debt, Fair Value	$ 919.3	$ 922.3

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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No definition available.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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- Definition

Fair value portion of other assets.

+ References

No definition available.

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