Fair Value Measurements (Tables)

6 Months Ended

Mar. 31, 2016

Fair Value Disclosures [Abstract]

Schedule of Financial Assets and Financial Liabilities that are Measured at Fair Value on a Recurring Basis

The following table presents on a gross basis our derivative assets and liabilities including both current and noncurrent portions, that are measured at fair value on a recurring basis within the fair value hierarchy, as of March 31, 2016, September 30, 2015 and March 31, 2015:

	Asset (Liability)
	Level 1			Level 2			Level 3		Total
March 31, 2016:
Assets:
Commodity contracts	$	1,179		$	—		$	—	$	1,179
Liabilities:
Commodity contracts	$	(3,281	)	$	(387	)	$	—	$	(3,668	)
September 30, 2015:
Assets:
Commodity contracts	$	934		$	373		$	—	$	1,307
Liabilities:
Commodity contracts	$	(4,560	)	$	(1,388	)	$	—	$	(5,948	)
Interest rate contracts	$	—		$	(7,016	)	$	—	$	(7,016	)
March 31, 2015:
Assets:
Commodity contracts	$	612		$	1		$	—	$	613
Liabilities:
Commodity contracts	$	(4,366	)	$	(1,174	)	$	—	$	(5,540	)