Supporting Financial Information - Accounts Payable, Accrued Expense and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accounts payable	$ 10,054	$ 3,393
Accrued benefits	2,252	2,060
Accrued bonus and incentive compensation	1,951	2,191
Accrued workers' compensation insurance	4,007	2,642
Other accrued expenses	2,369	664
Accounts payable, accrued expenses, and other current liabilities	$ 20,633	$ 10,950