Asset Retirement Obligations (Tables)

12 Months Ended

Sep. 30, 2021

Asset Retirement Obligation Disclosure [Abstract]

Rollforward of AROs

The following table provides a roll-forward of the AROs reflected in the Company’s Consolidated Balance Sheets:

	2021		2020
Beginning Balance	$	11,759	$	12,675
Purchase accounting in connection with the KMG Acquisition	—		(860)
Liabilities Settled	(21)		—
Accretion of discount	585		599
Estimate revision	(290)		(655)
Ending Balance at September 30	$	12,033	$	11,759