Summary of Significant Accounting Policies - Narrative (Details)		12 Months Ended
	Apr. 02, 2021 USD ($) segment	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Mar. 10, 2021 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for doubtful accounts		$ 0	$ 0
Depreciation expense		420,000	428,000
Number of reporting units | segment	2
Unrecognized tax benefits		0	0
Interest expense		$ 4,500,000	$ 5,300,000
Revenue Benchmark | Customer Concentration Risk | One Purchaser
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Concentration risk, percentage		87.00%	86.00%
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property and equipment, useful life		3 years
Contact term		1 year
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property and equipment, useful life		39 years
Contact term		10 years
Kansas Properties
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Goodwill	$ 19,000,000			$ 19,000,000
Discontinued operation, carrying value	22,000,000
Discontinued operation, fair value	$ 3,500,000
Goodwill impairment		$ 18,500,000
Kansas Properties
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Consideration				$ 3,500,000
General and Administrative Expense
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lease expense		$ 400,000	$ 400,000