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

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Amount, after tax and before reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Derivative Instruments and Hedging Activities - Effect of Derivative Financial Instruments on Net Income and Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives			$ 9,117	$ (24,602)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income	$ 0	$ (4,400)	(26,972)	(8,596)
Other non-interest income \| Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives			0	0
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income			(24,467)	0
Interest expense \| Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives	0	429	9,117	(24,602)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income	0	(4,400)	(2,505)	(8,596)
Derivative Designated as Hedging Instrument \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Income (Loss) Recognized in Earnings	0	0	0	0
Derivative Designated as Hedging Instrument \| Net interest income \| Interest Rate Swap \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Income (Loss) Recognized in Earnings	0	0	4,777	0
Derivative Designated as Hedging Instrument \| Net interest income \| Available-for-sale Securities \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Income (Loss) Recognized in Earnings	0	0	(4,777)	0
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Income (Loss) Recognized in Earnings	386	952	2,584	(4,379)
Not Designated as Hedging Instrument \| Other non-interest income \| Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Income (Loss) Recognized in Earnings	517	387	2,540	(6,191)
Not Designated as Hedging Instrument \| Other non-interest income \| Interest Rate Cap
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Income (Loss) Recognized in Earnings	0	0	0	0
Not Designated as Hedging Instrument \| Other non-interest income \| Credit Contract
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Income (Loss) Recognized in Earnings	7	162	81	1,436
Not Designated as Hedging Instrument \| Mortgage banking income \| Residential Mortgage Loan Commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Income (Loss) Recognized in Earnings	$ (138)	$ 403	$ (37)	$ 376