FAIR VALUE - Carrying Amounts and Fair Values of Company's Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Financial assets:
Available-for-sale debt securities	$ 1,140,783	$ 1,102,681
Held-to-maturity debt securities	177,854	200,411
Loans, net of allowance	11,403,565	11,246,124
Accrued interest receivable	45,627	46,583
Financial liabilities:
Time deposits	2,580,578
Other deposits	11,745,665	10,996,538
Advances from FHLB	250,000	550,000
Subordinated debt	371,400	370,803
Carrying Amount
Financial assets:
Cash and cash equivalents	518,963	545,898
Loans held for sale		10,836
Available-for-sale debt securities	1,140,783	1,102,681
Held-to-maturity debt securities	215,747	236,165
Other investments	61,714	75,607
Loans, net of allowance	11,403,565	11,246,124
Interest rate swap agreements	15,361	15,867
Accrued interest receivable	45,627	46,583
Bank owned life insurance	167,343	158,921
Financial liabilities:
Time deposits	2,580,578	2,714,555
Other deposits	9,165,087	8,281,983
Securities sold under retail repurchase agreements and federal funds purchased	68,911	375,032
Advances from FHLB	250,000	550,000
Subordinated debt	371,400	370,803
Interest rate swap agreements	15,361	15,867
Accrued interest payable	16,569	30,367
Carrying Amount | Residential mortgage loans held for sale
Financial assets:
Loans held for sale	22,757
Carrying Amount | SBA loans held for sale
Financial assets:
Loans held for sale	715
Estimated Fair Value
Financial assets:
Cash and cash equivalents	518,963	545,898
Loans held for sale		10,836
Available-for-sale debt securities	1,140,783	1,102,681
Held-to-maturity debt securities	177,854	200,411
Other investments	61,714	75,607
Loans, net of allowance	10,685,700	10,476,059
Interest rate swap agreements	15,361	15,867
Accrued interest receivable	45,627	46,583
Bank owned life insurance	167,343	158,921
Financial liabilities:
Time deposits	2,578,132	2,704,013
Other deposits	9,165,087	8,281,983
Securities sold under retail repurchase agreements and federal funds purchased	68,911	375,032
Advances from FHLB	248,749	547,271
Subordinated debt	395,176	348,185
Interest rate swap agreements	15,361	15,867
Accrued interest payable	16,569	30,367
Estimated Fair Value | Residential mortgage loans held for sale
Financial assets:
Loans held for sale	22,757
Estimated Fair Value | SBA loans held for sale
Financial assets:
Loans held for sale	763
Quoted Prices in Active Markets for Identical Assets (Level 1) | Estimated Fair Value
Financial assets:
Cash and cash equivalents	518,963	545,898
Loans held for sale		0
Available-for-sale debt securities	0	0
Held-to-maturity debt securities	0	0
Other investments	0	0
Loans, net of allowance	0	0
Interest rate swap agreements	0	0
Accrued interest receivable	45,627	46,583
Bank owned life insurance	0	0
Financial liabilities:
Time deposits	0	0
Other deposits	9,165,087	8,281,983
Securities sold under retail repurchase agreements and federal funds purchased	0	0
Advances from FHLB	0	0
Subordinated debt	0	0
Interest rate swap agreements	0	0
Accrued interest payable	16,569	30,367
Quoted Prices in Active Markets for Identical Assets (Level 1) | Estimated Fair Value | Residential mortgage loans held for sale
Financial assets:
Loans held for sale	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Estimated Fair Value | SBA loans held for sale
Financial assets:
Loans held for sale	0
Significant Other Observable Inputs (Level 2) | Estimated Fair Value
Financial assets:
Cash and cash equivalents	0	0
Loans held for sale		10,836
Available-for-sale debt securities	1,140,783	1,102,681
Held-to-maturity debt securities	177,854	200,411
Other investments	61,714	75,607
Loans, net of allowance	0	0
Interest rate swap agreements	15,361	15,867
Accrued interest receivable	0	0
Bank owned life insurance	167,343	158,921
Financial liabilities:
Time deposits	2,578,132	2,704,013
Other deposits	0	0
Securities sold under retail repurchase agreements and federal funds purchased	68,911	375,032
Advances from FHLB	248,749	547,271
Subordinated debt	0	0
Interest rate swap agreements	15,361	15,867
Accrued interest payable	0	0
Significant Other Observable Inputs (Level 2) | Estimated Fair Value | Residential mortgage loans held for sale
Financial assets:
Loans held for sale	22,757
Significant Other Observable Inputs (Level 2) | Estimated Fair Value | SBA loans held for sale
Financial assets:
Loans held for sale	763
Significant Unobservable Inputs (Level 3) | Estimated Fair Value
Financial assets:
Cash and cash equivalents	0	0
Loans held for sale		0
Available-for-sale debt securities	0	0
Held-to-maturity debt securities	0	0
Other investments	0	0
Loans, net of allowance	10,685,700	10,476,059
Interest rate swap agreements	0	0
Accrued interest receivable	0	0
Bank owned life insurance	0	0
Financial liabilities:
Time deposits	0	0
Other deposits	0	0
Securities sold under retail repurchase agreements and federal funds purchased	0	0
Advances from FHLB	0	0
Subordinated debt	395,176	348,185
Interest rate swap agreements	0	0
Accrued interest payable	0	$ 0
Significant Unobservable Inputs (Level 3) | Estimated Fair Value | Residential mortgage loans held for sale
Financial assets:
Loans held for sale	0
Significant Unobservable Inputs (Level 3) | Estimated Fair Value | SBA loans held for sale
Financial assets:
Loans held for sale	$ 0