Related Party Transactions - Shared Services Agreement (Details) - TBCO - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Related Party Transaction [Line Items]
Payments for services and covenants	$ 618
Expense under shared services agreement	592	$ 564	$ 479
Due to related parties	$ 163	$ 148

Carrying amount as of the balance sheet date of obligations due all related parties.

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