Long-term Debt (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Long-term debt, total	$ 623.5	$ 626.4
Less current portion	(3.9)	(3.9)
Long-term debt	619.6	622.5
Revolving Credit Facility [Member] \| Revolving Credit Facility due August 2017 [Member]
Debt Instrument [Line Items]
Long-term debt, total	$ 0.0	$ 0.0
Long term debt maturity date	Aug. 31, 2017	Aug. 31, 2017
Secured Debt [Member] \| Term Loan due May 2017 [Member]
Debt Instrument [Line Items]
Long-term debt, total	$ 373.5	$ 376.4
Long term debt maturity date	May 31, 2017	May 31, 2017
Senior Notes [Member] \| 4.875% Senior Notes due July 2024 [Member]
Debt Instrument [Line Items]
Long-term debt, total	$ 250.0	$ 250.0
Long term debt maturity date	Jul. 31, 2024	Jul. 31, 2024
Senior notes, interest rate	4.875%	4.875%

Contractual interest rate for funds borrowed, under the debt agreement.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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