Legal, Environmental, and Other Contingencies - Schedule of Maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Sep. 30, 2016
Environmental post-closure monitoring and maintenance activities	$ 683	$ 683
Long Term Obligations
Maturities of long-term obligations (discounted)
2017	75
2018	78
2019	59
2020	50
2021	50
2022 and thereafter	371
Long-term obligations (less current portion)	$ 683