Financial Instruments Other Comprehensive Income (Details) - USD ($) $ in Thousands		12 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Other Comprehensive Income [Abstract]
Interest rate agreements fair value		$ (71,003)	$ (58,973)
Forward commodity contracts fair value		(49,211)	7,904
Interest rate agreements		542	2,686
Forward commodity contracts		25,448	(5,102)
Total other comprehensive income (loss) from hedging, net of tax	[1]	(94,224)	(53,485)
Expected Earnings [Line Items]
2016		(19,831)
2017		(5,491)
2018		(1,468)
2019		(758)
2020		(703)
Thereafter		(15,836)
Cash Flow Hedge Gain (Loss) To Be Reclassiflied, Total	[2]	(44,087)
Interest Rate Contract [Member]
Other Comprehensive Income [Abstract]
Total other comprehensive income (loss) from hedging, net of tax		(70,461)	(56,287)	$ 82,179
Expected Earnings [Line Items]
2016		(347)
2017		(447)
2018		(649)
2019		(673)
2020		(698)
Thereafter		(15,836)
Cash Flow Hedge Gain (Loss) To Be Reclassiflied, Total	[2]	(18,650)
Commodity Contract [Member]
Other Comprehensive Income [Abstract]
Total other comprehensive income (loss) from hedging, net of tax		(23,763)	$ 2,802	$ 4,519
Expected Earnings [Line Items]
2016		(19,484)
2017		(5,044)
2018		(819)
2019		(85)
2020		(5)
Thereafter		0
Cash Flow Hedge Gain (Loss) To Be Reclassiflied, Total	[2]	$ (25,437)

[1] Utilizing an income tax rate ranging from approximately 37 percent to 39 percent based on the effective rates in each taxing jurisdiction.

[2] Utilizing an income tax rate ranging from approximately 37 percent to 39 percent based on the effective rates in each taxing jurisdiction.