Retirement and Post-Retirement Employee Benefit Plans Net Periodic Cost (Details) (USD $)	0 Months Ended	12 Months Ended
	Apr. 02, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		$ 15,345,000	$ 17,754,000	$ 15,084,000
Interest cost		22,330,000	19,334,000	21,568,000
Expected return on assets		(23,601,000)	(22,955,000)	(21,474,000)
Amortization of prior service cost		(136,000)	(141,000)	(141,000)
Recognized actuarial loss		13,777,000	19,066,000	14,451,000
Net periodic pension cost		27,715,000	33,058,000	29,488,000
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		16,784,000	18,800,000	16,353,000
Interest cost		15,951,000	12,964,000	13,861,000
Expected return on assets		(5,167,000)	(3,988,000)	(2,607,000)
Amortization of transition asset		274,000	1,081,000	1,511,000
Amortization of prior service cost		(1,450,000)	(1,450,000)	(1,450,000)
Recognized actuarial loss		631,000	4,196,000	2,648,000
Net periodic pension cost		27,023,000	31,603,000	30,316,000
Supplemental Executive Retirement Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		3,607,000	3,039,000	2,108,000
Interest cost		4,966,000	4,755,000	5,142,000
Amortization of transition asset		0	0	0
Amortization of prior service cost		0	0	0
Recognized actuarial loss		1,948,000	2,918,000	2,118,000
Settlements	(3,200,000)	4,539,000	3,160,000	0
Effect on Net Periodic Cost Due To Discount Rate Change, Remaining Fiscal Year	100,000
Net periodic pension cost		$ 15,060,000	$ 13,872,000	$ 9,368,000