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Benefit Plans Asset Holdings (Details)	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Defined Benefit Plan Disclosure
Target Allocation	100.00%
Plan Asset Allocations	100.00%	100.00%
Equity securities
Defined Benefit Plan Disclosure
New Policy Target Allocation	47.00%
Target Allocation	39.00%
Plan Asset Allocations	44.00%	43.00%
Fixed income
Defined Benefit Plan Disclosure
New Policy Target Allocation	30.00%
Public real assets
Defined Benefit Plan Disclosure
Target Allocation	15.00%
Plan Asset Allocations	15.00%	14.00%
Private equity funds
Defined Benefit Plan Disclosure
Target Allocation	8.00%
Plan Asset Allocations	4.00%	5.00%
Low volatility global public equity [Member]
Defined Benefit Plan Disclosure
Target Allocation	15.00%
Plan Asset Allocations	18.00%	19.00%
Cash
Defined Benefit Plan Disclosure
Target Allocation	15.00%
Plan Asset Allocations	10.00%	10.00%
Private real assets
Defined Benefit Plan Disclosure
New Policy Target Allocation	23.00%
Target Allocation	8.00%
Plan Asset Allocations	9.00%	9.00%

X

- Definition

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

+ References

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- Definition

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
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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