Summary of Significant Accounting Policies - Accrued Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Sep. 30, 2021
Accounting Policies [Abstract]
Accrued capital expenditures	$ 15,520	$ 9,718
Accrued lease operating expenses	2,692	2,428
Accrued general and administrative costs	2,363	3,575
Other accrued expenditures	1,396	2,834
Total accrued liabilities	$ 21,971	$ 18,555

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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