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Stock-Based and Other Long-Term Incentive Compensation - Restricted Stock, Narrative (Details) $ in Millions						9 Months Ended
	Jun. 30, 2023 shares	May 09, 2023 independent_director shares	Apr. 25, 2023 shares	Aug. 15, 2022 executive_officer shares	Apr. 26, 2022 independent_director shares	Sep. 30, 2023 USD ($) shares	Sep. 30, 2022 USD ($)
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)						153,656
Canceled/Forfeited (in shares)						14,357
Share-based compensation expense | $						$ 1.7	$ 1.0
Restricted Stock | Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)					4,212
Number of independent directors | independent_director					3
Award vesting period					1 year
Restricted Stock | Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)				32,040
Award vesting period				3 years
Number of executive officers | executive_officer				2
Canceled/Forfeited (in shares)			11,024
Restricted Stock | Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			58,790	60,839
Restricted Stock | Chief Technical Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			27,840
Award vesting period			3 years
Restricted Stock Units (RSUs) | Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		9,470
Number of independent directors | independent_director		4
Award vesting period		1 year
Restricted Stock Units (RSUs) | Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	10,101
Award vesting period	1 year

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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