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OTHER INCOME (EXPENSE) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Other Income and Expenses [Abstract] |  |  |  |
Foreign currency transaction gain (loss), before tax | $ 72 | $ 150 | $ 441 | $ 535
Net periodic benefit income | 392 | 787 | 1,170 | 2,361
Investment income, net | $ 294 | $ (14) | 145 | $ 18
Contract award income |  |  | $ 700 |

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