FAIR VALUE - Financial Assets and Liabilities at Dates Indicated that were Accounted for at Fair Value (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	$ 1,259,945	$ 1,465,896
Held-to-maturity debt securities:	275,834	0
Residential mortgage loans held for sale (at fair value)	17,537	39,409
Residential mortgage loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale (at fair value)	17,500	38,200
U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	105,498	68,539
State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	321,853	326,402
Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	832,594	1,070,955
Held-to-maturity debt securities:	275,834	0
Fair Value, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	1,259,945	1,465,896
Held-to-maturity debt securities:	275,834
Total assets	1,561,555	1,511,185
Total liabilities	(8,239)	(5,880)
Fair Value, Recurring \| Residential mortgage loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale	17,537	39,409
Fair Value, Recurring \| U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	105,498	68,539
Fair Value, Recurring \| State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	321,853	326,402
Fair Value, Recurring \| Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	832,594	1,070,955
Held-to-maturity debt securities:	275,834
Fair Value, Recurring \| Interest rate swap agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	8,239	5,880
Interest rate swap agreements	(8,239)	(5,880)
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	0	0
Held-to-maturity debt securities:	0
Total assets	0	0
Total liabilities	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Residential mortgage loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	0	0
Held-to-maturity debt securities:	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Interest rate swap agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	0	0
Interest rate swap agreements	0	0
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	1,259,945	1,465,896
Held-to-maturity debt securities:	275,834
Total assets	1,561,555	1,511,185
Total liabilities	(8,239)	(5,880)
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Residential mortgage loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale	17,537	39,409
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	105,498	68,539
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	321,853	326,402
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	832,594	1,070,955
Held-to-maturity debt securities:	275,834
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Interest rate swap agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	8,239	5,880
Interest rate swap agreements	(8,239)	(5,880)
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	0	0
Held-to-maturity debt securities:	0
Total assets	0	0
Total liabilities	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Residential mortgage loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total available-for-sale debt securities	0	0
Held-to-maturity debt securities:	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Interest rate swap agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	0	0
Interest rate swap agreements	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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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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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.

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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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- Definition

Fair value of financial and nonfinancial obligations.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of other assets.

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Fair value portion of other liabilities.

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