Debt (Details) - USD ($) $ in Millions	Jun. 26, 2020	Dec. 27, 2019
Current maturities of long-term debt
Debt Issuance Costs, Current, Net	$ 0.2	$ 0.9
Long-term Debt, Current Maturities	19.7	634.5
Long-term debt
Long-term Debt	5,273.4	4,788.3
Total Debt	5,293.1	5,422.8
Debt Issuance Costs	50.0	47.1
Total Debt Issuance Costs	50.2	48.0
Term Loan due 2025 \| Secured Debt
Current maturities of long-term debt
Debt Issuance Costs, Current, Net	0.1	0.1
Long-term Debt, Current Maturities	4.1	4.1
Long-term debt
Long-term Debt	397.4	399.5
Debt Issuance Costs	5.5	6.1
Loans Payable	401.5	403.6
Term Loan due 2024 \| Secured Debt
Current maturities of long-term debt
Debt Issuance Costs, Current, Net	0.1	0.2
Long-term Debt, Current Maturities	15.6	15.6
Long-term debt
Long-term Debt	1,497.4	1,505.2
Debt Issuance Costs	13.9	15.5
Loans Payable	1,513.0	1,520.8
4.88% Senior Notes \| Unsecured Debt
Current maturities of long-term debt
Debt Issuance Costs, Current, Net	0.0	0.6
Long-term Debt, Current Maturities	0.0	614.8
Long-term debt
Long-term Debt		614.8
9.50% Debenture \| Debentures
Long-term debt
Long-term Debt	10.4	10.4
Debt Issuance Costs	0.0	0.0
5.75% Senior Notes \| Unsecured Debt
Long-term debt
Long-term Debt	610.3	610.3
Debt Issuance Costs	2.9	3.7
8.00% Debenture \| Debentures
Long-term debt
Long-term Debt	4.4	4.4
Debt Issuance Costs	0.0	0.0
4.75% Senior Notes \| Unsecured Debt
Long-term debt
Long-term Debt	133.7	133.7
Debt Issuance Costs	0.6	0.8
5.625% Senior Notes \| Unsecured Debt
Long-term debt
Long-term Debt	514.7	514.7
Debt Issuance Costs	3.8	4.4
5.50% Senior Notes \| Unsecured Debt
Long-term debt
Long-term Debt	387.2	387.2
Debt Issuance Costs	3.3	3.6
2017 Revolving Credit Facility \| Secured Debt
Long-term debt
Long-term Debt	900.0	900.0
Debt Issuance Costs	2.4	3.1
10.00% Second Lien Senior Notes \| Unsecured Debt
Long-term debt
Long-term Debt	322.9	322.9
Debt Issuance Costs	9.0	9.9
10.00% First Lien Senior Notes \| Unsecured Debt
Long-term debt
Long-term Debt	495.0	0.0
Debt Issuance Costs	$ 8.6	$ 0.0

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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