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		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives			$ 9,117	$ (25,031)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income	$ (1,046)	$ (2,718)	(26,972)	(4,196)
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	4	(4,685)	9,117	(25,031)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income	(1,046)	(2,718)	(2,505)	(4,196)
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	(130)	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	130	0	(4,777)	0
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Income (Loss) Recognized in Earnings	(334)	(4,322)	2,198	(5,331)
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	(376)	(5,563)	2,023	(6,578)
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	(63)	1,405	74	1,274
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	$ 105	$ (164)	$ 101	$ (27)