Pension and Other Postretirement Benefits (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Apr. 30, 2016 |
Apr. 30, 2015 |
Apr. 30, 2016 |
Apr. 30, 2015 |
|
| Pension Plan | ||||
| Defined Benefit Plans and Other Postretirement Benefit Plans | ||||
| Service cost | $ 370 | $ 402 | $ 1,126 | $ 1,205 |
| Interest cost | 479 | 463 | 1,446 | 1,388 |
| Expected return on plan assets | (480) | (470) | (1,442) | (1,409) |
| Amortization of Prior service costs | 2 | 2 | 6 | 7 |
| Amortization of Other actuarial loss | 239 | 144 | 735 | 433 |
| Net periodic benefit cost | 610 | 541 | 1,871 | 1,624 |
| Postretirement Health Plan | ||||
| Defined Benefit Plans and Other Postretirement Benefit Plans | ||||
| Service cost | 27 | 33 | 70 | 100 |
| Interest cost | 21 | 26 | 62 | 79 |
| Amortization of Net transition obligation | 0 | 1 | 0 | 1 |
| Amortization of Prior service costs | (2) | (2) | (5) | (5) |
| Amortization of Other actuarial loss | 0 | 10 | 0 | 28 |
| Net periodic benefit cost | $ 46 | $ 68 | $ 127 | $ 203 |