Commitments and Contingencies (Details) $ in Millions	3 Months Ended
	Dec. 31, 2019 USD ($) Bcf
Commitments and Contingencies Disclosure [Abstract]
Self-insurance retention expense | $	$ 1.0
Short-term Contract with Customer | Supply Commitment
Long-term Purchase Commitment [Line Items]
Long-term purchase commitment, minimum volume required	25,700
Long-term Contract with Customer | Supply Commitment
Long-term Purchase Commitment [Line Items]
Long-term purchase commitment, minimum volume required	1,000.0