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Derivatives and Hedging Activity - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2020
Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Settlement value of interest rate contracts hedges	$ 66.0
Notional value of contracts settled	350.0
Derivative contracts settlement value net of tax.	$ 49.4
Scenario, Forecast [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Estimated pretax loss to be reclassified from accumulated other comprehensive loss into earnings		$ 5.5

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- Definition

Derivative contracts settled notional amount.

+ References

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- Definition

Derivative contracts settlement value.

+ References

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- Definition

Derivative contracts settlement value net of tax.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80845-113994

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