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Pension Plans (Details 3) - Pension Plan, Defined Benefit [Member] - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2011
Post-retirement plan |  |  |
Fair values of plan assets | $ 609.7 | $ 609.7 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 609.7 |  |
Fair value of plan assets at end of year | 672.3 | 609.7 |
Cash and Cash Equivalents [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 11.0 | 11.0 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 11.0 |  |
Fair value of plan assets at end of year | 7.9 | 11.0 |
Diversified Funds [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 108.6 | 108.6 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 108.6 |  |
Fair value of plan assets at end of year | 159.3 | 108.6 |
Equity Funds [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 192.4 | 192.4 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 192.4 |  |
Fair value of plan assets at end of year | 220.3 | 192.4 |
Fixed Income Funds [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 220.6 | 220.6 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 220.6 |  |
Fair value of plan assets at end of year | 219.3 | 220.6 |
Hedge Funds [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 25.0 | 25.0 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 25.0 |  |
Fair value of plan assets at end of year | 27.9 | 25.0 |
Assets Held by Insurance Company [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 46.1 | 46.1 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 46.1 |  |
Fair value of plan assets at end of year | 37.6 | 46.1 |
Real Estate [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 6.0 | 6.0 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 6.0 |  |
Fair value of plan assets at end of year |  | 6.0 |
Fair Value, Inputs, Level 1 [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 11.0 | 11.0 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 11.0 |  |
Fair value of plan assets at end of year | 3.4 | 11.0 |
Fair Value, Inputs, Level 1 [Member] | Cash and Cash Equivalents [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 11.0 | 11.0 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 11.0 |  |
Fair value of plan assets at end of year | 3.4 | 11.0 |
Fair Value, Inputs, Level 2 |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 586.1 | 586.1 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 586.1 |  |
Fair value of plan assets at end of year | 655.2 | 586.1 |
Fair Value, Inputs, Level 2 | Cash and Cash Equivalents [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 4.5 |  |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at end of year | 4.5 |  |
Fair Value, Inputs, Level 2 | Diversified Funds [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 108.6 | 108.6 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 108.6 |  |
Fair value of plan assets at end of year | 159.3 | 108.6 |
Fair Value, Inputs, Level 2 | Equity Funds [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 192.4 | 192.4 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 192.4 |  |
Fair value of plan assets at end of year | 220.3 | 192.4 |
Fair Value, Inputs, Level 2 | Fixed Income Funds [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 220.6 | 220.6 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 220.6 |  |
Fair value of plan assets at end of year | 219.3 | 220.6 |
Fair Value, Inputs, Level 2 | Hedge Funds [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 12.4 | 12.4 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 12.4 |  |
Fair value of plan assets at end of year | 14.2 | 12.4 |
Fair Value, Inputs, Level 2 | Assets Held by Insurance Company [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 46.1 | 46.1 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 46.1 |  |
Fair value of plan assets at end of year | 37.6 | 46.1 |
Fair Value, Inputs, Level 2 | Real Estate [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 6.0 | 6.0 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 6.0 |  |
Fair value of plan assets at end of year |  | 6.0 |
Fair Value, Inputs, Level 3 [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 12.6 | 10.6 |
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 12.6 | 10.6 |
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 1.1 | 2.0 |
Fair value of plan assets at end of year | 13.7 | 12.6 |
Fair Value, Inputs, Level 3 [Member] | Hedge Funds [Member] |  |  |
Post-retirement plan |  |  |
Fair values of plan assets | 12.6 | 12.6 | $ 10.6
Changes in the fair value of Level 3 assets |  |  |
Fair value of plan assets at beginning of year | 12.6 |  |
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 1.1 | 2.0 |
Fair value of plan assets at end of year | $ 13.7 | $ 12.6 |

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- Definition Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 50 -URI http://asc.fasb.org/extlink&oid=29635418&loc=d3e12355-114930 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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