Derivative Financial Instruments - Offsetting of Derivative Assets (Detail) - Zero Cost Collars [Member] - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Asset Derivatives, Gross amounts of recognized assets	$ 262	$ 1,456
Asset Derivatives, Net amounts of assets presented in the balance sheets	262	1,456
Asset Derivatives, Gross amounts not offset in the balance sheets, Cash collateral pledged	0	1,070
Asset Derivatives, Net amount	$ 262	$ 2,526

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

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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Fair value, after offset of derivative liability, of 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, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after effects of master netting arrangements, of 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 offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

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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.

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No definition available.

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