FAIR VALUE - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	$ 6,081,120	$ 6,453,761
Mortgage Backed Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	3,517,827	4,044,443
Fair Value, Measurements, Recurring [Member]
Assets Fair Value Disclosure [Abstract]
Equity Securities, FV-NI	5,082	5,378
Derivative Assets	1,025	1,505
Derivative Liabilities [Abstract]
Derivative Liabilities	636	1,178
Fair Value, Measurements, Recurring [Member] \| Other Available For Sale Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	1,000	1,000
Fair Value, Measurements, Recurring [Member] \| U S Treasury Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	141,347	148,486
Fair Value, Measurements, Recurring [Member] \| Mortgage Backed Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	3,517,827	4,044,443
Fair Value, Measurements, Recurring [Member] \| Government Agencies Debt Securities [Member] \| Noncallable [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	258,663	285,028
Fair Value, Measurements, Recurring [Member] \| Government Agencies Debt Securities [Member] \| Call Option [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	2,159,474	1,971,954
Fair Value, Measurements, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	2,809	2,850
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 1 [Member]
Assets Fair Value Disclosure [Abstract]
Equity Securities, FV-NI	5,082	5,378
Derivative Assets	0	0
Derivative Liabilities [Abstract]
Derivative Liabilities	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 1 [Member] \| Other Available For Sale Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 1 [Member] \| U S Treasury Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	141,347	148,486
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 1 [Member] \| Mortgage Backed Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 1 [Member] \| Government Agencies Debt Securities [Member] \| Noncallable [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 1 [Member] \| Government Agencies Debt Securities [Member] \| Call Option [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 1 [Member] \| US States and Political Subdivisions Debt Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 2 [Member]
Assets Fair Value Disclosure [Abstract]
Equity Securities, FV-NI	0	0
Derivative Assets	1,025	1,505
Derivative Liabilities [Abstract]
Derivative Liabilities	636	1,178
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 2 [Member] \| Other Available For Sale Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 2 [Member] \| U S Treasury Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 2 [Member] \| Mortgage Backed Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	3,511,456	4,037,209
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 2 [Member] \| Government Agencies Debt Securities [Member] \| Noncallable [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	258,663	285,028
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 2 [Member] \| Government Agencies Debt Securities [Member] \| Call Option [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	2,159,474	1,971,954
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 2 [Member] \| US States and Political Subdivisions Debt Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 3 [Member]
Assets Fair Value Disclosure [Abstract]
Equity Securities, FV-NI	0	0
Derivative Assets	0	0
Derivative Liabilities [Abstract]
Derivative Liabilities	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 3 [Member] \| Other Available For Sale Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	1,000	1,000
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 3 [Member] \| U S Treasury Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 3 [Member] \| Mortgage Backed Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	6,371	7,234
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 3 [Member] \| Government Agencies Debt Securities [Member] \| Noncallable [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 3 [Member] \| Government Agencies Debt Securities [Member] \| Call Option [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value Inputs Level 3 [Member] \| US States and Political Subdivisions Debt Securities [Member]
Assets Fair Value Disclosure [Abstract]
Debt Securities, Available-for-sale	$ 2,809	$ 2,850

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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