Credit exposure to settled variation margin in excess of customer related interest rate swap.

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- Definition

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

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- Definition

Fair value of credit risk derivative asset after deduction of credit risk derivative liability.

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- Definition

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 increase (decrease) in the fair value of derivatives recognized in the income statement.

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Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities 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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Nominal or face amount used to calculate payment on derivative.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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- Definition

Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Derivative Financial Instruments - Additional information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Derivative [Line Items]
Maximum length of time hedged in cash flow hedge			5 years
Credit exposure to settled variation margin in excess of customer related interest rate swap	$ 600,000		$ 600,000		$ 400,000
Notional Amount	2,400,000,000		2,400,000,000
Derivative, gain (loss) on derivative, net (less than during both the three months ended September 30, 2022 and September 30, 2021)	(100,000)	$ (100,000)	(200,000)	$ (500,000)
Derivative asset	24,360,000		24,360,000		64,714,000
Derivative liability (less than as of September 30, 2022)	86,290,000		86,290,000		18,593,000
Loan Origination Commitments
Derivative [Line Items]
Notional Amount	9,400,000		9,400,000		31,900,000
Derivative asset	100,000		100,000		300,000
Derivative liability (less than as of September 30, 2022)	100,000		100,000		100,000
Forward Contracts
Derivative [Line Items]
Notional Amount	8,100,000		8,100,000		24,400,000
Non Cleared Derivative Transactions \| Customer Related Interest Rate Swap Derivatives
Derivative [Line Items]
Fair value of interest rate swap liabilities that are net in a net liability position	0		0		13,700,000
Cash and Cash Equivalents \| Non Cleared Derivative Transactions \| Customer Related Interest Rate Swap Derivatives
Derivative [Line Items]
Additional collateral posted	2,000,000		2,000,000
Available-for-sale Securities \| Non Cleared Derivative Transactions \| Customer Related Interest Rate Swap Derivatives
Derivative [Line Items]
Additional collateral posted					21,300,000
Restricted Assets \| Cash and Cash Equivalents \| Cleared Derivative Transaction
Derivative [Line Items]
Additional collateral posted	83,700,000		83,700,000
Restricted Assets \| Available-for-sale Securities \| Cleared Derivative Transaction
Derivative [Line Items]
Additional collateral posted					$ 48,900,000
Interest Income \| Active Cash Flow Hedges
Derivative [Line Items]
Interest rate swap cash flow hedges amount expected to reclassified from other comprehensive income to income statement in the next twelve months	27,600,000		27,600,000
Interest Income \| Termination Of Cash Flow Hedges
Derivative [Line Items]
Interest rate swap cash flow hedges amount expected to reclassified from other comprehensive income to income statement in the next twelve months	$ 600,000		$ 600,000