Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Accumulated balances for each classification of comprehensive income (loss)
Balance at the beginning of the period	$ (68.9)	$ (29.4)	$ (61.8)	$ (31.5)	$ (31.5)
Other comprehensive loss before reclassifications	(9.2)	(18.1)	(17.7)	(17.0)
Amounts reclassified from accumulated other comprehensive loss	1.1	0.9	3.5	2.6
Income tax benefit (expense)	(0.4)	(0.3)	(1.4)	(1.0)
Other comprehensive loss	(8.5)	(17.5)	(15.6)	(15.4)	(30.3)
Balance at the end of the period	(77.4)	(46.9)	(77.4)	(46.9)	(61.8)
Accrued post-retirement benefit liability
Accumulated balances for each classification of comprehensive income (loss)
Balance at the beginning of the period	(30.4)	(27.6)	(32.0)	(28.2)	(28.2)
Other comprehensive loss before reclassifications				(0.6)
Amounts reclassified from accumulated other comprehensive loss	1.3	1.1	3.9	3.1
Income tax benefit (expense)	(0.5)	(0.4)	(1.5)	(1.2)
Other comprehensive loss	0.8	0.7	2.4	1.3
Balance at the end of the period	(29.6)	(26.9)	(29.6)	(26.9)	(32.0)
Foreign currency translation
Accumulated balances for each classification of comprehensive income (loss)
Balance at the beginning of the period	(38.9)	(2.6)	(30.4)	(4.3)	(4.3)
Other comprehensive loss before reclassifications	(9.2)	(18.1)	(17.7)	(16.4)
Other comprehensive loss	(9.2)	(18.1)	(17.7)	(16.4)
Balance at the end of the period	(48.1)	(20.7)	(48.1)	(20.7)	(30.4)
Hedging activities
Accumulated balances for each classification of comprehensive income (loss)
Balance at the beginning of the period	0.4	0.8	0.6	1.0	1.0
Amounts reclassified from accumulated other comprehensive loss	(0.2)	(0.2)	(0.4)	(0.5)
Income tax benefit (expense)	0.1	0.1	0.1	0.2
Other comprehensive loss	(0.1)	(0.1)	(0.3)	(0.3)
Balance at the end of the period	$ 0.3	$ 0.7	$ 0.3	$ 0.7	$ 0.6

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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