DERIVATIVES - Summary of Derivative Financial Instruments and Balances (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 11,875,690	$ 7,586,618
Derivative Asset	272,499	112,607
Estimate Fair Value Loss	(272,606)	(112,616)
Fair Value Hedges \| Matched interest rate swaps \| Accrued interest and other liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,300,336	1,923,375
Derivative Asset	107	2,636
Estimate Fair Value Loss	(184,884)	(70,808)
Fair Value Hedges \| Matched interest rate swaps \| Accrued interest and other assets
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,300,336	1,923,375
Derivative Asset	184,777	70,799
Estimate Fair Value Loss	(107)	(2,636)
Foreign Exchange [Member] \| Matched interest rate swaps \| Accrued interest and other liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	3,637,509	1,869,934
Derivative Asset	27,249	10,433
Estimate Fair Value Loss	(60,366)	(28,739)
Foreign Exchange [Member] \| Matched interest rate swaps \| Accrued interest and other assets
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	3,637,509	1,869,934
Derivative Asset	60,366	28,739
Estimate Fair Value Loss	(27,249)	(10,433)
Derivative [Member] \| Accrued interest and other liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,300,000	1,900,000
Estimate Fair Value Loss	$ (182,300)	$ (67,500)

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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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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Nominal or face amount used to calculate payment on derivative.

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