Accounts and Financing Receivables - Summary of Allowance for Doubtful Accounts (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2020 USD ($)
Receivables [Abstract]
Balance at October 1, 2019	$ 951
Bad debt expense, net of recoveries	63
Write-offs	(518)
Balance at September 30, 2020	$ 496