Postretirement Benefit Plans - Defined Contribution Plan Expenses for Company's Qualified Contribution Plans (Detail) - USD ($) $ in Thousands |
3 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Defined Contribution Plan Disclosure [Line Items] | ||
| Total defined contribution plan expenses | $ 2,805 | $ 3,325 |
| Retirement Savings Contributions [Member] | ||
| Defined Contribution Plan Disclosure [Line Items] | ||
| Total defined contribution plan expenses | 2,244 | 2,215 |
| Profit Sharing Contributions [Member] | ||
| Defined Contribution Plan Disclosure [Line Items] | ||
| Total defined contribution plan expenses | $ 561 | $ 1,110 |