Financing - Components of Long-Term Debt (Detail) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Debt Instrument [Line Items]
Total debt	$ 380.3	$ 380.8	$ 397.5
Less: Current portion of capital lease obligations	1.0	1.0	0.7
Non-current portion of debt	379.3	379.8	396.8
ABL Facility [Member]
Debt Instrument [Line Items]
Long-term debt	0.0	0.0	16.5
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Long-term debt	375.0	375.0	375.0
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Obligations under capital lease	$ 5.3	$ 5.8	$ 6.0

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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