Debt - Components of Debt (Detail) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 30, 2017
Debt
Principal	$ 1,282.7	$ 2,313.5
Unamortized Debt Issuance Costs	18.5	26.5
Net	1,252.0	2,057.5
Other debt financing	0.0	0.8
Total debt	1,264.2	2,287.0
Short-term borrowings and current debt
ABL facility	0.0	220.3
Total short-term borrowings required to be repaid or extinguished as part of divestiture	0.0	220.3
GE Term Loan - current maturities	0.0	2.0
Short-term borrowings	6.9	0.0
Capital leases - current maturities	1.8	2.3
Total current debt	8.7	225.4
Debt required to be repaid or extinguished as part of divestiture [Abstract]
Principal	0.0	525.0
Unamortized Debt Issuance Costs	0.0	6.0
Net	0.0	519.0
Short-term borrowings
Debt
Principal	6.9	0.0
Unamortized Debt Issuance Costs	0.0	0.0
Net	6.9	0.0
Long-term Debt
Debt
Principal	1,274.0	1,563.1
Unamortized Debt Issuance Costs	18.5	20.5
Debt required to be repaid or extinguished as part of divestiture [Abstract]
Total long-term debt	1,255.5	1,542.6
ABL facility
Debt
Principal	0.0	220.3
Unamortized Debt Issuance Costs	0.0	0.0
Net	0.0	220.3
GE Term Loan
Debt
Principal	0.0	2.0
Unamortized Debt Issuance Costs	0.0	0.0
Net	0.0	2.0
Capital leases
Debt
Principal	5.3	6.4
Capital leases	5.3	6.4
10.000% senior notes due in 2021
Debt
Principal	0.0	269.9
Unamortized Debt Issuance Costs	0.0	0.0
Net	0.0	269.9
Debt required to be repaid or extinguished as part of divestiture [Abstract]
Debt instrument, unamortized premium		19.9
5.375% senior notes due in 2022
Debt
Principal	0.0	525.0
Unamortized Debt Issuance Costs	0.0	6.0
Net	0.0	519.0
Debt required to be repaid or extinguished as part of divestiture [Abstract]
Principal	0.0	525.0
Unamortized Debt Issuance Costs	0.0	6.0
Net	0.0	519.0
5.500% senior notes due in 2024
Debt
Principal	520.5	539.1
Unamortized Debt Issuance Costs	8.1	9.5
Net	512.4	529.6
5.500% senior notes due in 2025
Debt
Principal	750.0	750.0
Unamortized Debt Issuance Costs	10.4	11.0
Net	$ 739.6	$ 739.0

Debt required to be repaid or extinguished as part of divestiture [Abstract]

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Long term debt and capital lease obligations face amount.

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Long term debt required to be repaid or extinguished from divestiture.

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Long term debt required to be repaid or extinguished from divestiture face amount.

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Unamortized debt issuance expense long term debt required to be repaid or extinguished from divestiture.

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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 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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Face (par) amount of debt instrument at time of issuance.

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Amount, after accumulated amortization, of debt premium.

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The carrying value as of the balance sheet date of the current portion 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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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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Carrying value at the balance sheet date of the current portion of a financial instrument used to receive debt funding on a regular basis with original maturities ranging from 5-10 years.

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Amount of long-term notes classified as other, payable within one year or the normal operating cycle, if longer.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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