FAIR VALUES OF FINANCIAL INSTRUMENTS - Fair Value Measurements of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	$ 1,500,136	$ 1,976,661
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	1,713	2,459
Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	1,495,195	1,970,763
Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	3,228	3,439
Recurring | Derivative liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	114,014	92,770
Recurring | U.S. Treasury
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	1,713	2,459
Recurring | U.S. Government-sponsored agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	93,585	101,962
Recurring | State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	973,056	1,351,760
Recurring | U.S. Government-sponsored mortgage-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	419,963	508,273
Recurring | Corporate obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	11,819	12,207
Recurring | Derivative assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	114,541	93,036
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Derivative liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0	0
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Treasury
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	1,713	2,459
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Government-sponsored agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0	0
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0	0
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Government-sponsored mortgage-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0	0
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0	0
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Derivative assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Recurring | Significant Other Observable Inputs (Level 2) | Derivative liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	114,014	92,770
Recurring | Significant Other Observable Inputs (Level 2) | U.S. Treasury
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0	0
Recurring | Significant Other Observable Inputs (Level 2) | U.S. Government-sponsored agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	93,585	101,962
Recurring | Significant Other Observable Inputs (Level 2) | State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	969,863	1,348,356
Recurring | Significant Other Observable Inputs (Level 2) | U.S. Government-sponsored mortgage-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	419,959	508,269
Recurring | Significant Other Observable Inputs (Level 2) | Corporate obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	11,788	12,176
Recurring | Significant Other Observable Inputs (Level 2) | Derivative assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	114,541	93,036
Recurring | Significant Unobservable Inputs (Level 3) | Derivative liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0	0
Recurring | Significant Unobservable Inputs (Level 3) | U.S. Treasury
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0	0
Recurring | Significant Unobservable Inputs (Level 3) | U.S. Government-sponsored agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0	0
Recurring | Significant Unobservable Inputs (Level 3) | State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	3,193	3,404
Recurring | Significant Unobservable Inputs (Level 3) | U.S. Government-sponsored mortgage-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	4	4
Recurring | Significant Unobservable Inputs (Level 3) | Corporate obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	31	31
Recurring | Significant Unobservable Inputs (Level 3) | Derivative assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	$ 0	$ 0