Loans and Allowance for Credit Losses - Rollforward of Allowance for Credit/Loan Losses by Portfolio Segment (Detail) - USD ($) |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jan. 31, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||||
| Beginning balance | $ 429,233,000 | $ 373,488,000 | $ 421,162,000 | $ 261,734,000 | |
| PCD allowance for credit loss at acquisition | $ 85,299,000 | 15,167,000 | 77,293,000 | ||
| Charge-offs | (17,780,000) | (16,895,000) | (39,367,000) | (53,862,000) | |
| Recoveries | 1,919,000 | 1,433,000 | 4,577,000 | 2,528,000 | |
| Provision | 28,000,000 | 21,000,000 | 55,000,000 | 106,500,000 | |
| Ending balance - ACL | 441,372,000 | 394,193,000 | 441,372,000 | 394,193,000 | |
| Beginning balance - ACL on off-balance sheet | 5,721,000 | 8,221,000 | 5,721,000 | 4,138,000 | |
| Initial allowance for credit loss at acquisition | 3,583,000 | ||||
| Provision | 0 | 0 | 500,000 | ||
| Ending balance - ACL on off-balance sheet | 5,721,000 | 8,221,000 | 5,721,000 | 8,221,000 | |
| Commercial and Industrial Portfolio [Member] | |||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||||
| Beginning balance | 252,669,000 | 192,755,000 | 240,324,000 | 161,553,000 | |
| PCD allowance for credit loss at acquisition | 9,883,000 | 45,026,000 | |||
| Charge-offs | (8,923,000) | (6,112,000) | (12,272,000) | (32,108,000) | |
| Recoveries | 422,000 | 120,000 | 1,512,000 | 189,000 | |
| Provision | 51,144,000 | 14,082,000 | 65,748,000 | 36,068,000 | |
| Ending balance - ACL | 295,312,000 | 210,728,000 | 295,312,000 | 210,728,000 | |
| Beginning balance - ACL on off-balance sheet | 3,865,000 | 5,535,000 | 2,886,000 | 2,234,000 | |
| Initial allowance for credit loss at acquisition | 2,166,000 | ||||
| Provision | 96,000 | (1,204,000) | 1,075,000 | (69,000) | |
| Ending balance - ACL on off-balance sheet | 3,961,000 | 4,331,000 | 3,961,000 | 4,331,000 | |
| Commercial Real Estate Portfolio [Member] | |||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||||
| Beginning balance | 146,435,000 | 149,345,000 | 151,060,000 | 77,340,000 | |
| PCD allowance for credit loss at acquisition | 5,284,000 | 32,048,000 | |||
| Charge-offs | (1,173,000) | (4,178,000) | (11,937,000) | (6,502,000) | |
| Recoveries | 26,000 | 184,000 | 29,000 | 184,000 | |
| Provision | (33,292,000) | 2,854,000 | (27,156,000) | 50,419,000 | |
| Ending balance - ACL | 111,996,000 | 153,489,000 | 111,996,000 | 153,489,000 | |
| Beginning balance - ACL on off-balance sheet | 1,608,000 | 2,412,000 | 2,548,000 | 1,741,000 | |
| Initial allowance for credit loss at acquisition | 1,192,000 | ||||
| Provision | (197,000) | 1,128,000 | (1,137,000) | 607,000 | |
| Ending balance - ACL on off-balance sheet | 1,411,000 | 3,540,000 | 1,411,000 | 3,540,000 | |
| Consumer Real Estate Portfolio [Member] | |||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||||
| Beginning balance | 5,134,000 | 4,798,000 | 6,938,000 | 4,327,000 | |
| PCD allowance for credit loss at acquisition | 206,000 | ||||
| Charge-offs | (386,000) | (400,000) | (899,000) | (1,629,000) | |
| Recoveries | 22,000 | 147,000 | 41,000 | 163,000 | |
| Provision | 940,000 | 976,000 | (370,000) | 2,454,000 | |
| Ending balance - ACL | 5,710,000 | 5,521,000 | 5,710,000 | 5,521,000 | |
| Beginning balance - ACL on off-balance sheet | 116,000 | 138,000 | 154,000 | 70,000 | |
| Initial allowance for credit loss at acquisition | 63,000 | ||||
| Provision | (17,000) | 42,000 | (55,000) | 47,000 | |
| Ending balance - ACL on off-balance sheet | 99,000 | 180,000 | 99,000 | 180,000 | |
| Consumer Portfolio [Member] | |||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||||
| Beginning balance | 1,319,000 | 1,488,000 | 1,387,000 | 966,000 | |
| PCD allowance for credit loss at acquisition | 13,000 | ||||
| Charge-offs | (972,000) | (681,000) | (2,057,000) | (1,423,000) | |
| Recoveries | 154,000 | 126,000 | 453,000 | 245,000 | |
| Provision | 1,470,000 | 634,000 | 2,188,000 | 1,766,000 | |
| Ending balance - ACL | 1,971,000 | 1,567,000 | 1,971,000 | 1,567,000 | |
| Beginning balance - ACL on off-balance sheet | 77,000 | 91,000 | 91,000 | 16,000 | |
| Initial allowance for credit loss at acquisition | 41,000 | ||||
| Provision | 6,000 | 7,000 | (8,000) | 41,000 | |
| Ending balance - ACL on off-balance sheet | 83,000 | 98,000 | 83,000 | 98,000 | |
| Credit Cards Portfolio [Member] | |||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||||
| Beginning balance | 18,531,000 | 19,995,000 | 18,042,000 | 14,272,000 | |
| Charge-offs | (6,326,000) | (5,524,000) | (12,202,000) | (12,200,000) | |
| Recoveries | 1,295,000 | 856,000 | 2,522,000 | 1,747,000 | |
| Provision | 4,590,000 | 2,586,000 | 9,728,000 | 14,094,000 | |
| Ending balance - ACL | 18,090,000 | 17,913,000 | 18,090,000 | 17,913,000 | |
| Leases and Other Portfolio [Member] | |||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||||
| Beginning balance | 1,788,000 | 541,000 | 1,727,000 | 631,000 | |
| Recoveries | 20,000 | ||||
| Provision | 2,509,000 | 159,000 | 2,550,000 | 69,000 | |
| Ending balance - ACL | 4,297,000 | 700,000 | 4,297,000 | 700,000 | |
| Beginning balance - ACL on off-balance sheet | 31,000 | 35,000 | 27,000 | 63,000 | |
| Initial allowance for credit loss at acquisition | 114,000 | ||||
| Provision | 114,000 | 19,000 | 118,000 | (123,000) | |
| Ending balance - ACL on off-balance sheet | 145,000 | 54,000 | 145,000 | 54,000 | |
| Total - Loans [Member] | |||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||||
| Beginning balance | 425,876,000 | 368,922,000 | 419,478,000 | 259,089,000 | |
| PCD allowance for credit loss at acquisition | 15,167,000 | 77,293,000 | |||
| Charge-offs | (17,780,000) | (16,895,000) | (39,367,000) | (53,862,000) | |
| Recoveries | 1,919,000 | 1,433,000 | 4,577,000 | 2,528,000 | |
| Provision | 27,361,000 | 21,291,000 | 52,688,000 | 104,870,000 | |
| Ending balance - ACL | 437,376,000 | 389,918,000 | 437,376,000 | 389,918,000 | |
| Beginning balance - ACL on off-balance sheet | 5,697,000 | 8,211,000 | 5,706,000 | 4,124,000 | |
| Initial allowance for credit loss at acquisition | 3,576,000 | ||||
| Provision | 2,000 | (8,000) | (7,000) | 503,000 | |
| Ending balance - ACL on off-balance sheet | 5,699,000 | 8,203,000 | 5,699,000 | 8,203,000 | |
| HTM [Member] | |||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||||
| Beginning balance | 3,357,000 | 4,566,000 | 1,684,000 | 2,645,000 | |
| Provision | 639,000 | (291,000) | 2,312,000 | 1,630,000 | |
| Ending balance - ACL | 3,996,000 | 4,275,000 | 3,996,000 | 4,275,000 | |
| Beginning balance - ACL on off-balance sheet | 24,000 | 10,000 | 15,000 | 14,000 | |
| Initial allowance for credit loss at acquisition | 7,000 | ||||
| Provision | (2,000) | 8,000 | 7,000 | (3,000) | |
| Ending balance - ACL on off-balance sheet | $ 22,000 | $ 18,000 | $ 22,000 | $ 18,000 | |