Financing - Components of Long-Term Debt (Detail) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Total debt	$ 313.4	$ 316.0
Less: Current portion of debt	(4.6)	(4.5)
Noncurrent portion of debt	308.8	311.5
Term Loan Facility [Member]
Debt Instrument [Line Items]
Long-term debt	316.8	319.2
Deferred financing fees and discount on debt	(6.1)	(6.9)
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Obligations under capital lease	$ 2.7	$ 3.7

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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
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Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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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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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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