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Investments in Unconsolidated Affiliates Hamer (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 9 Months Ended
--- | --- | --- | ---
Sep. 30, 2015 | Jun. 30, 2015 | Sep. 30, 2014 | Jun. 30, 2014 | Jun. 30, 2015 | Jun. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Equity Method Investment, Realized Gain (Loss) on Disposal | $ 20.0 |  |  |  |  |  |  |
Equity in earnings of unconsolidated affiliates, net of tax | $ 3.9 |  | $ 7.0 |  |  |  | $ 18.0 | $ 33.3
Hamer, LLC [Member] |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Equity in earnings of unconsolidated affiliates, net of tax |  | $ 1.1 |  | $ 0.4 | $ 1.6 | $ 0.8 |  |

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