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Pension Benefit Obligations (Details 3) - Pension Plan, Defined Benefit - USD ($) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2015 | Sep. 30, 2014
Post-retirement plan |  |
Fair values of plan assets | $ 672.3 | $ 672.3
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 672.3 |
Fair value of plan assets at end of year | 1,384.8 | 672.3
Cash and Cash Equivalents |  |
Post-retirement plan |  |
Fair values of plan assets | 7.9 | 7.9
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 7.9 |
Fair value of plan assets at end of year | 44.4 | 7.9
Global equity securities |  |
Post-retirement plan |  |
Fair values of plan assets | 52.8 |
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at end of year | 52.8 |
Domestic equity securities |  |
Post-retirement plan |  |
Fair values of plan assets | 60.0 |
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at end of year | 60.0 |
Diversified Funds |  |
Post-retirement plan |  |
Fair values of plan assets | 159.3 | 159.3
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 159.3 |
Fair value of plan assets at end of year | 287.4 | 159.3
Equity Funds |  |
Post-retirement plan |  |
Fair values of plan assets | 220.3 | 220.3
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 220.3 |
Fair value of plan assets at end of year | 309.6 | 220.3
Fixed Income Funds |  |
Post-retirement plan |  |
Fair values of plan assets | 219.3 | 219.3
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 219.3 |
Fair value of plan assets at end of year | 542.5 | 219.3
Hedge Funds |  |
Post-retirement plan |  |
Fair values of plan assets | 27.9 | 27.9
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 27.9 |
Fair value of plan assets at end of year | 53.0 | 27.9
Assets Held by Insurance Company |  |
Post-retirement plan |  |
Fair values of plan assets | 37.6 | 37.6
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 37.6 |
Fair value of plan assets at end of year | 35.1 | 37.6
Level 1 |  |
Post-retirement plan |  |
Fair values of plan assets | 3.4 | 3.4
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 3.4 |
Fair value of plan assets at end of year | 11.0 | 3.4
Level 1 | Cash and Cash Equivalents |  |
Post-retirement plan |  |
Fair values of plan assets | 3.4 | 3.4
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 3.4 |
Fair value of plan assets at end of year | 11.0 | 3.4
Level 2 |  |
Post-retirement plan |  |
Fair values of plan assets | 655.2 | 655.2
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 655.2 |
Fair value of plan assets at end of year | 1,360.2 | 655.2
Level 2 | Cash and Cash Equivalents |  |
Post-retirement plan |  |
Fair values of plan assets | 4.5 | 4.5
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 4.5 |
Fair value of plan assets at end of year | 33.4 | 4.5
Level 2 | Global equity securities |  |
Post-retirement plan |  |
Fair values of plan assets | 52.8 |
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at end of year | 52.8 |
Level 2 | Domestic equity securities |  |
Post-retirement plan |  |
Fair values of plan assets | 60.0 |
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at end of year | 60.0 |
Level 2 | Diversified Funds |  |
Post-retirement plan |  |
Fair values of plan assets | 159.3 | 159.3
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 159.3 |
Fair value of plan assets at end of year | 287.4 | 159.3
Level 2 | Equity Funds |  |
Post-retirement plan |  |
Fair values of plan assets | 220.3 | 220.3
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 220.3 |
Fair value of plan assets at end of year | 309.6 | 220.3
Level 2 | Fixed Income Funds |  |
Post-retirement plan |  |
Fair values of plan assets | 219.3 | 219.3
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 219.3 |
Fair value of plan assets at end of year | 542.5 | 219.3
Level 2 | Hedge Funds |  |
Post-retirement plan |  |
Fair values of plan assets | 14.2 | 14.2
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 14.2 |
Fair value of plan assets at end of year | 39.4 | 14.2
Level 2 | Assets Held by Insurance Company |  |
Post-retirement plan |  |
Fair values of plan assets | 37.6 | 37.6
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 37.6 |
Fair value of plan assets at end of year | 35.1 | 37.6
Level 3 |  |
Post-retirement plan |  |
Fair values of plan assets | 13.7 | 13.7
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 13.7 |
Fair value of plan assets at end of year | 13.6 | 13.7
Level 3 | Hedge Funds |  |
Post-retirement plan |  |
Fair values of plan assets | 13.7 | 12.6
Changes in the fair value of Level 3 assets |  |
Fair value of plan assets at beginning of year | 13.7 | 12.6
Defined Benefit Plan, Actual Return on Plan Assets Still Held | (0.1) | 1.1
Fair value of plan assets at end of year | $ 13.6 | $ 13.7

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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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