Long-Term Debt and Lines of Credit - Schedule of Interest Costs Expensed and Capitalized (Details) - USD ($) $ in Thousands  | 
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Mar. 31, 2017  | 
Mar. 31, 2016  | 
Mar. 31, 2017  | 
Mar. 31, 2016  | 
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| Debt Disclosure [Abstract] | ||||
| Interest expense | $ 2,374 | $ 2,475 | $ 4,701 | $ 4,978 | 
| Interest capitalized | 64 | 38 | 127 | 81 | 
| Total | $ 2,438 | $ 2,513 | $ 4,828 | $ 5,059 | 
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- References No definition available. 
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- Definition Amount of interest capitalized during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Total interest costs incurred during the period and either capitalized or charged against earnings. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of the cost of borrowed funds accounted for as interest expense. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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