Fair Value of Financial Instruments - Narrative (Detail)	Sep. 30, 2020 $ / Contract
Investment in unconsolidated affiliates \| Income-Approach
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, strike price	0

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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Balance Type:	na
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