Legal, Environmental and Other Contingencies - Schedule of Maturities (Details) $ in Thousands	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($)	Feb. 11, 2016 item
Environmental post-closure monitoring and maintenance activities	$ 633	$ 633
Maturities of long-term obligations (discounted)
Number of leaks reported in entity's chemical cleaning operations | item			1
Long Term Obligations
Maturities of long-term obligations (discounted)
2019	54
2020	52
2021	60
2022	50
2023 and thereafter	315
Long-term obligations (less current portion)	$ 531