Debt Securities, Pledged As Collateral, Available-for-sale, Restricted

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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- Definition

Average fixed interest rate that will be received or paid upon exercise of a group of interest rate swaption contracts.

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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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Nominal or face amount used to calculate payment on derivative.

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The number of derivative instruments of a particular group held by the entity.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Derivatives - Additional Information (Detail)	12 Months Ended
Derivatives - Additional Information (Detail)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jun. 30, 2016 USD ($) derivative
Derivative [Line Items]
Interest expense	$ 41,155,000	$ 60,453,000	$ 39,562,000
Estimated reclassification next fiscal year until maturity	(129,000)
Interest Rate Swap
Derivative [Line Items]
Debt securities, pledged as collateral, available-for-sale, restricted	83,200,000	$ 30,000,000.0
Cash Flow Hedging \| Interest Rate Swap
Derivative [Line Items]
Number of derivatives \| derivative				2
Notional amount				$ 30,000,000.0
Average interest rate				1.10%
Cash Flow Hedging \| Interest Rate Swap \| Reclassification Out of Accumulated Other Comprehensive Income
Derivative [Line Items]
Interest expense	$ 50,000