Debt - Fair Value of Long-Term Debt (Details) - USD ($)	Dec. 31, 2017	Dec. 25, 2016
Debt Disclosure [Abstract]
Principal	$ 300,800,000.0	$ 437,300,000.0
Carrying Amount	294,300,000	432,000,000
Fair Value	312,700,000	423,600,000
Original issue discount		2,400,000
Debt issuance costs	6,500,000	$ 2,900,000
Maturities of long-term debt in 2018	$ 800,000

No definition available.

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- Definition

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

+ References

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Amount, after accumulated amortization, of debt discount.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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