Investment Securities - Proceeds from Sale, Gross Gains (Losses) Realized on Sales, Maturities and Other-Than-Temporary Impairment Charges Related to Securities Available for Sale (Detail) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Net Investment Income [Line Items] | ||||
| Proceeds from maturities and redemptions of available-for-sale securities | $ 0 | $ 69,862 | ||
| Gain Losses Maturities And Impairment | $ 311 | $ 0 | 540 | (5,142) |
| Sales | ||||
| Net Investment Income [Line Items] | ||||
| Gross Gains | 0 | 0 | ||
| Gross Losses | 0 | (5,142) | ||
| Gain Losses Maturities And Impairment | 0 | (5,142) | ||
| Maturities | ||||
| Net Investment Income [Line Items] | ||||
| Gross Gains | 540 | 0 | ||
| Gross Losses | 0 | 0 | ||
| Gain Losses Maturities And Impairment | $ 540 | $ 0 | ||