Retirement Benefits (Details 4)	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015
Equity Securities [Member]
Asset Allocation
Minimum	40.00%
Maximum	65.00%
Target Allocation	52.00%
As of the balance sheet date	50.00%	48.00%
Debt Securities [Member]
Asset Allocation
Minimum	30.00%
Maximum	50.00%
Target Allocation	39.00%
As of the balance sheet date	41.00%	43.00%
Other Security [Member]
Asset Allocation
Minimum	0.00%
Maximum	15.00%
Target Allocation	9.00%
As of the balance sheet date	9.00%	9.00%

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Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
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Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

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Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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