Long-Term Debt - Summary of Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 26, 2021	Dec. 26, 2020
Debt Instrument [Line Items]
Capital & finance leases	$ 1,773	$ 2,044
Long-term debt, capital and finance leases	1,665,217	1,549,792
Unamortized premium on 11.6% Junior Subordinated Debentures	13,777	14,591
Unamortized discount on Senior term loan	5,783	6,532
Current portion of long term debt, capital leases and finance leases	(11,442)	(11,481)
Deferred financing fees	10,293	10,862
Long-term debt	1,651,476	1,535,508
Revolving loans
Debt Instrument [Line Items]
Long-term debt, gross	158,000	72,000
Senior term loan, due 2025
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,066,740	1,037,044
6.375% Senior Notes, due 2022
Debt Instrument [Line Items]
Debt instrument, stated rate	6.375%
Long-term debt, gross	$ 330,000	330,000
11.6% Junior Subordinated Debentures - Preferred
Debt Instrument [Line Items]
Debt instrument, stated rate	11.60%
Long-term debt, gross	$ 105,443	105,443
Junior Subordinated Debentures - Common
Debt Instrument [Line Items]
Long-term debt, gross	$ 3,261	$ 3,261

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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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt premium.

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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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Present value of lessee's discounted obligation for lease payments from finance lease.

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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 of long-term debt and lease obligation, classified as current.

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Amount of long-term debt and lease obligation, including portion classified as current.

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