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Stock-Based and Other Long-Term Incentive Compensation - Restricted Stock, Narrative (Details) $ in Thousands						9 Months Ended
	Jun. 17, 2022	Mar. 18, 2022	Jun. 17, 2021 shares	Apr. 01, 2021 shares	Mar. 18, 2021 independent_director shares	Sep. 30, 2021 USD ($) shares	Sep. 30, 2020 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation expense \| $						$ 0
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)						156,339
Share-based compensation expense \| $						$ 1,300	$ 1,700
Total unrecognized compensation expense \| $						$ 1,800
Recognition period						1 year 8 months 12 days
Restricted Stock \| Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)					109,212
Award vesting period					3 years
Restricted Stock \| Chief Financial Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			5,000		20,000
Restricted Stock \| Vice President of Technical Services
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			5,000		20,000
Restricted Stock \| Executive Officers \| Forecast
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years	3 years
Restricted Stock \| Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)				5,291	5,612
Award vesting period					1 year
Number of independent directors \| independent_director					3