Derivative Instruments and Hedging Activities - Additional Information (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2021 USD ($) derivative	Dec. 31, 2020 USD ($) derivative
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, net liability position, aggregate fair value	$ (33,200)
Minimum
Derivative Instruments, Gain (Loss) [Line Items]
Derivative expiration period	30 days
Maximum
Derivative Instruments, Gain (Loss) [Line Items]
Derivative expiration period	60 days
Not Designated as Hedging Instrument \| Residential mortgage loan commitments
Derivative Instruments, Gain (Loss) [Line Items]
Aggregate notional amount	$ 8,700	$ 11,900
Interest Rate Contract
Derivative Instruments, Gain (Loss) [Line Items]
Cash collateral pledged	$ 31,693	$ 97,641
Interest Rate Contract \| Derivative Designated as Hedging Instrument \| Cash Flow Hedges
Derivative Instruments, Gain (Loss) [Line Items]
Number of outstanding interest rate derivatives \| derivative	0	5
Aggregate notional amount		$ 1,100,000
Number of interest rate derivatives terminated \| derivative	4
Aggregate notional amount, terminated	$ 850,000
Reclassification of realized losses from AOCI, discontinuation of cash flow hedge	$ 25,900
Interest Rate Contract \| Derivative Designated as Hedging Instrument \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Number of outstanding interest rate derivatives \| derivative	16	24
Aggregate notional amount	$ 80,500	$ 272,300
Number of interest rate derivatives terminated \| derivative	8
Aggregate notional amount, terminated	$ 191,800
Interest Rate Swap \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Aggregate notional amount	$ 1,400,000	$ 1,400,000
Number of derivative instruments held \| derivative	155	155
Interest Rate Cap \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Aggregate notional amount	$ 265,600	$ 204,900
Number of derivative instruments held \| derivative	14,000	12,000
Credit Contract \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Aggregate notional amount	$ 162,200	$ 177,200

Derivative, Notional Amount, Terminated

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Number of Interest Rate Derivatives Terminated

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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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.

+ References

No definition available.

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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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- Definition

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

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- Definition

Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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Number of interest rate derivative instruments held by the entity at the reporting date.

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Amount, before tax, of reclassification from accumulated other comprehensive income (AOCI) for gain (loss) from discontinuance of cash flow hedge included in assessment of hedge effectiveness.

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