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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%

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