Long-Term Debt - Summary of Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 27, 2020	Dec. 28, 2019
Debt Instrument [Line Items]
Capital & finance leases	$ 2,112	$ 2,275
Long-term debt, capital and finance leases	1,612,165	1,601,632
Unamortized premium on 11.6% Junior Subordinated Debentures	15,366	16,110
Unamortized discount on Senior term loan	7,285	8,040
Current portion of long term debt, capital leases and finance leases	(11,400)	(11,358)
Deferred financing fees	12,458	14,055
Long-term debt	1,596,388	1,584,289
Revolving loans
Debt Instrument [Line Items]
Long-term debt, gross	129,000	113,000
Senior term loan, due 2025
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,042,349	1,047,653
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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Present value of lessee's discounted obligation for lease payments from finance lease.

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

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