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Shareholders' Equity - AOCI Reclassifications (Details) - USD ($) $ in Thousands | 3 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015
Accumulated Other Comprehensive Income (loss) |  |
Accumulated other comprehensive income (loss) components which were reclassified to the Consolidated Statement of Operations |  |
Total reclassifications for the period | $ 366 |
Defined benefit pension plan |  |
Accumulated other comprehensive income (loss) components which were reclassified to the Consolidated Statement of Operations |  |
Total reclassifications for the period | 366 | $ 313
Defined benefit pension plan | Income tax provision |  |
Accumulated other comprehensive income (loss) components which were reclassified to the Consolidated Statement of Operations |  |
Reclassifications for the period, tax | (209) | (180)
Amortization of net actuarial loss | General and Administrative |  |
Accumulated other comprehensive income (loss) components which were reclassified to the Consolidated Statement of Operations |  |
Reclassifications for the period, before tax | $ 575 | $ 493

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