Retirement Benefit Obligations - Schedule of Weighted-Average Asset Allocations, by Asset Category (Detail) |
Jun. 30, 2023 |
Jun. 30, 2022 |
|---|---|---|
| Asset Category: | ||
| Benefit plan weighted-average asset allocations | 100.00% | 100.00% |
| Equity Securities | ||
| Asset Category: | ||
| Benefit plan weighted-average asset allocations | 15.00% | 15.00% |
| Debt securities | ||
| Asset Category: | ||
| Benefit plan weighted-average asset allocations | 72.00% | 75.00% |
| Cash And Other | ||
| Asset Category: | ||
| Benefit plan weighted-average asset allocations | 13.00% | 10.00% |