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Shareholders' Equity - AOCI Reclassifications (Details) - USD ($) $ in Thousands	3 Months Ended
	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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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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