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Retirement Plans (Strategic Allocation of Plan Assets) (Details) | 12 Months Ended |
--- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2013
Strategic asset allocation |  |  |
Defined Benefit Plan, Target Plan Asset Allocations | 100.00% |  |
Actual asset allocations |  |  |
Actual plan asset allocations | 100.00% | 100.00% | 100.00%
Equity Securities [Member] |  |  |
Strategic asset allocation |  |  |
Defined Benefit Plan, Target Plan Asset Allocations | 40.00% |  |
Equity investments tactical range, minimum | 30.00% |  |
Equity investments tactical range, maximum | 50.00% |  |
Actual asset allocations |  |  |
Actual plan asset allocations | 39.00% | 40.00% | 40.00%
Large Capitalization Stocks [Member] |  |  |
Strategic asset allocation |  |  |
Defined Benefit Plan, Target Plan Asset Allocations | 26.00% |  |
Small Capitalization Stocks [Member] |  |  |
Strategic asset allocation |  |  |
Defined Benefit Plan, Target Plan Asset Allocations | 5.00% |  |
International Stocks [Member] |  |  |
Strategic asset allocation |  |  |
Defined Benefit Plan, Target Plan Asset Allocations | 9.00% |  |
Fixed Income Funds [Member] |  |  |
Strategic asset allocation |  |  |
Defined Benefit Plan, Target Plan Asset Allocations |  | 60.00% |
Equity investments tactical range, minimum | 50.00% |  |
Equity investments tactical range, maximum | 70.00% |  |
Actual asset allocations |  |  |
Actual plan asset allocations | 60.00% | 59.00% | 59.00%
Cash and Cash Equivalents [Member] |  |  |
Strategic asset allocation |  |  |
Defined Benefit Plan, Target Plan Asset Allocations | 0.00% |  |
Equity investments tactical range, minimum | 0.00% |  |
Equity investments tactical range, maximum | 5.00% |  |
Actual asset allocations |  |  |
Actual plan asset allocations | 1.00% | 1.00% | 1.00%

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