Derivative Financial Instruments - Additional Information (Detail) - Senior Term Note Due July 1, 2026 [Member] $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($)
Derivative [Line Items]
Settlement of forward starting swap agreements	$ 9.2
Amortized period on interest expense	10 years

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.

No definition available.

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