Schedule of long-term Debt (Detail) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016	Jan. 31, 2015
Debt Instrument [Line Items]
Capital leases	$ 7.4	$ 4.6
Current portion of long-term debt	(3.1)	(2.3)
Long-term debt, net	376.4	354.2
Senior Secured Notes
Debt Instrument [Line Items]
Principal amount outstanding	305.0	305.0	$ 305.0
Unamortized original issue discount and debt issuance costs	(7.9)	(10.1)
Senior Secured Notes, net	297.1	294.9
Term Loan
Debt Instrument [Line Items]
Term Loan		1.5
Revolving Credit Facilities
Debt Instrument [Line Items]
Principal amount outstanding	76.0	57.0
Unamortized original issue discount and debt issuance costs	(1.0)	(1.5)
Revolving credit facilities, net	$ 75.0	$ 55.5

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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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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