FAIR VALUE DISCLOSURES OF FINANCIAL ASSETS AND LIABILITIES - Schedule of Financial Instruments Carried at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	$ 3,548,077	$ 3,510,648
Collateralized mortgage obligations (CMO)
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	428,883	430,942
Fannie Mae (FNMA) mortgage-backed securities (MBS)
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	2,789,404	2,755,579
Freddie Mac (FHLMC) MBS
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	106,010	105,514
Ginnie Mae (GNMA) MBS
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	40,384	40,676
Government-sponsored enterprises (GSE) agency notes
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	183,396	177,937
Fair Value, Measurements, Recurring
Assets measured at fair value on a recurring basis:
Other assets	149,781	170,489
Liabilities measured at fair value on a recurring basis:
Other liabilities	137,122	160,512
Assets measured at fair value on a nonrecurring basis:
Total assets measured at fair value	3,697,858	3,681,137
Fair Value, Measurements, Recurring | Collateralized mortgage obligations (CMO)
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	428,883	430,942
Fair Value, Measurements, Recurring | Fannie Mae (FNMA) mortgage-backed securities (MBS)
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	2,789,404	2,755,579
Fair Value, Measurements, Recurring | Freddie Mac (FHLMC) MBS
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	106,010	105,514
Fair Value, Measurements, Recurring | Ginnie Mae (GNMA) MBS
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	40,384	40,676
Fair Value, Measurements, Recurring | Government-sponsored enterprises (GSE) agency notes
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	183,396	177,937
Fair Value, Measurements, Nonrecurring
Assets measured at fair value on a nonrecurring basis:
Other real estate owned	5,204	5,204
Total assets measured at fair value	73,174	70,419
Fair Value, Measurements, Nonrecurring | Other investments
Assets measured at fair value on a nonrecurring basis:
Other investments	15,489	15,516
Fair Value, Measurements, Nonrecurring | Loans held for sale
Assets measured at fair value on a nonrecurring basis:
Loans held for sale	52,481	49,699
Quoted Prices in Active Markets for Identical Asset (Level 1) | Fair Value, Measurements, Recurring
Assets measured at fair value on a recurring basis:
Other assets	0	0
Liabilities measured at fair value on a recurring basis:
Other liabilities	0	0
Assets measured at fair value on a nonrecurring basis:
Total assets measured at fair value	0	0
Quoted Prices in Active Markets for Identical Asset (Level 1) | Fair Value, Measurements, Recurring | Collateralized mortgage obligations (CMO)
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	0	0
Quoted Prices in Active Markets for Identical Asset (Level 1) | Fair Value, Measurements, Recurring | Fannie Mae (FNMA) mortgage-backed securities (MBS)
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	0	0
Quoted Prices in Active Markets for Identical Asset (Level 1) | Fair Value, Measurements, Recurring | Freddie Mac (FHLMC) MBS
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	0	0
Quoted Prices in Active Markets for Identical Asset (Level 1) | Fair Value, Measurements, Recurring | Ginnie Mae (GNMA) MBS
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	0	0
Quoted Prices in Active Markets for Identical Asset (Level 1) | Fair Value, Measurements, Recurring | Government-sponsored enterprises (GSE) agency notes
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	0	0
Quoted Prices in Active Markets for Identical Asset (Level 1) | Fair Value, Measurements, Nonrecurring
Assets measured at fair value on a nonrecurring basis:
Other real estate owned	0	0
Total assets measured at fair value	0	0
Quoted Prices in Active Markets for Identical Asset (Level 1) | Fair Value, Measurements, Nonrecurring | Other investments
Assets measured at fair value on a nonrecurring basis:
Other investments	0	0
Quoted Prices in Active Markets for Identical Asset (Level 1) | Fair Value, Measurements, Nonrecurring | Loans held for sale
Assets measured at fair value on a nonrecurring basis:
Loans held for sale	0	0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Assets measured at fair value on a recurring basis:
Other assets	149,748	170,464
Liabilities measured at fair value on a recurring basis:
Other liabilities	132,509	155,242
Assets measured at fair value on a nonrecurring basis:
Total assets measured at fair value	3,697,825	3,681,112
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Collateralized mortgage obligations (CMO)
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	428,883	430,942
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Fannie Mae (FNMA) mortgage-backed securities (MBS)
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	2,789,404	2,755,579
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Freddie Mac (FHLMC) MBS
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	106,010	105,514
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Ginnie Mae (GNMA) MBS
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	40,384	40,676
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Government-sponsored enterprises (GSE) agency notes
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	183,396	177,937
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Nonrecurring
Assets measured at fair value on a nonrecurring basis:
Other real estate owned	0	0
Total assets measured at fair value	52,481	49,699
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Nonrecurring | Other investments
Assets measured at fair value on a nonrecurring basis:
Other investments	0	0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Nonrecurring | Loans held for sale
Assets measured at fair value on a nonrecurring basis:
Loans held for sale	52,481	49,699
Significant Unobservable Inputs (Level 3)
Assets measured at fair value on a recurring basis:
Other assets	33	25
Assets measured at fair value on a nonrecurring basis:
Other investments	15,489	15,516
Other real estate owned	5,204	5,204
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Assets measured at fair value on a recurring basis:
Other assets	33	25
Liabilities measured at fair value on a recurring basis:
Other liabilities	4,613	5,270
Assets measured at fair value on a nonrecurring basis:
Total assets measured at fair value	33	25
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Collateralized mortgage obligations (CMO)
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Fannie Mae (FNMA) mortgage-backed securities (MBS)
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Freddie Mac (FHLMC) MBS
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Ginnie Mae (GNMA) MBS
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Government-sponsored enterprises (GSE) agency notes
Assets measured at fair value on a recurring basis:
Investment securities available-for-sale	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Nonrecurring
Assets measured at fair value on a nonrecurring basis:
Other real estate owned	5,204	5,204
Total assets measured at fair value	20,693	20,720
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Nonrecurring | Other investments
Assets measured at fair value on a nonrecurring basis:
Other investments	15,489	15,516
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Nonrecurring | Loans held for sale
Assets measured at fair value on a nonrecurring basis:
Loans held for sale	$ 0	$ 0