Retirement Benefits (Details 4)	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Equity Securities [Member]
Asset Allocation
Minimum	40.00%
Maximum	65.00%
Target Allocation	51.00%
As of the balance sheet date	48.00%	50.00%
Debt Securities [Member]
Asset Allocation
Minimum	30.00%
Maximum	50.00%
Target Allocation	39.00%
As of the balance sheet date	43.00%	42.00%
Other Security [Member]
Asset Allocation
Minimum	0.00%
Maximum	15.00%
Target Allocation	10.00%
As of the balance sheet date	9.00%	8.00%