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Debt (Details) - USD ($) $ in Millions	Jul. 01, 2022	Jun. 16, 2022	Dec. 31, 2021
Current maturities of long-term debt
Debt Issuance Costs, Current, Net	$ 0.0		$ 6.1
Long-term Debt, Current Maturities	44.1		1,395.0
Long-term debt
Long-term Debt	3,048.0		0.0
Debt Issuance Costs	22.5		0.0
Total Debt Issuance Costs	22.5		6.1
Total Debt	3,092.1		5,145.8
Liabilities Subject to Compromise	0.0		(6,397.7)
Long-term Debt, Excluding Current Maturities	3,559.7
Debt Instrument, Face Amount	3,603.8
Long-term Debt
Long-term debt
Liabilities Subject to Compromise	0.0		(3,750.8)
Liabilities Subject to Compromise
Long-term debt
Total Debt Issuance Costs	0.0		0.0
Term Loan due 2025
Long-term debt
Secured Debt	0.0		370.7
Debt Instrument, Face Amount	0.0
Term Loan due 2025 \| Secured Debt
Long-term debt
Total Debt Issuance Costs	0.0		0.0
Term Loan due 2024
Long-term debt
Secured Debt	0.0		1,396.5
Debt Instrument, Face Amount	0.0
Term Loan due 2024 \| Secured Debt
Long-term debt
Total Debt Issuance Costs	0.0		0.0
9.50% Debenture
Long-term debt
Unsecured Debt	0.0		10.4
Debt Instrument, Face Amount	0.0
9.50% Debenture \| Unsecured Debt
Long-term debt
Total Debt Issuance Costs	0.0		0.0
5.75% Senior Notes
Long-term debt
Unsecured Debt	0.0		610.3
Debt Instrument, Face Amount	0.0
5.75% Senior Notes \| Unsecured Debt
Long-term debt
Total Debt Issuance Costs	0.0		0.0
8.00% Debenture
Long-term debt
Unsecured Debt	0.0		4.4
Debt Instrument, Face Amount	0.0
8.00% Debenture \| Unsecured Debt
Long-term debt
Total Debt Issuance Costs	0.0		0.0
4.75% Senior Notes
Long-term debt
Unsecured Debt	0.0		133.7
Debt Instrument, Face Amount	0.0
4.75% Senior Notes \| Unsecured Debt
Long-term debt
Total Debt Issuance Costs	0.0		0.0
5.625% Senior Notes
Long-term debt
Unsecured Debt	0.0		514.7
Debt Instrument, Face Amount	0.0
5.625% Senior Notes \| Unsecured Debt
Long-term debt
Total Debt Issuance Costs	0.0		0.0
5.50% Senior Notes
Long-term debt
Unsecured Debt	0.0		387.2
Debt Instrument, Face Amount	0.0
5.50% Senior Notes \| Unsecured Debt
Long-term debt
Total Debt Issuance Costs	0.0		0.0
10.00% Second Lien Senior Notes
Long-term debt
Secured Debt	228.4		0.0
Debt Instrument, Face Amount	322.9	$ 322.9
10.00% Second Lien Senior Notes \| Secured Debt
Long-term debt
Total Debt Issuance Costs	0.0		0.0
10.00% First Lien Senior Notes
Long-term debt
Secured Debt	471.9		495.0
Debt Instrument, Face Amount	495.0	495.0
10.00% First Lien Senior Notes \| Secured Debt
Long-term debt
Total Debt Issuance Costs	0.0		5.9
2017 Revolving Credit Facility
Long-term debt
Total Debt Issuance Costs	0.0		0.2
Secured Debt	0.0		900.0
Unsecured Debt			900.0
Debt Instrument, Face Amount	0.0
2017 Replacement Term Loan
Long-term debt
Total Debt Issuance Costs	0.0		0.0
Secured Debt	1,223.4		0.0
Total Debt	1,391.5
Debt Instrument, Face Amount	1,391.5	1,392.9
2018 Replacement Term Loan
Long-term debt
Total Debt Issuance Costs	0.0		0.0
Secured Debt	327.5		0.0
Total Debt	369.4
Debt Instrument, Face Amount	369.4	369.7
Eleven Point Five Percent First Lien Senior Secured Notes
Long-term debt
Total Debt Issuance Costs	22.5		0.0
Secured Debt	650.0		0.0
Debt Instrument, Face Amount	650.0	650.0
Ten Point Zero Percent Second Lien Notes due 2029
Long-term debt
Total Debt Issuance Costs	0.0		0.0
Secured Debt	190.9		0.0
Debt Instrument, Face Amount	375.0	375.0
Ten Point Zero Percent Second Lien Notes (Existing Notes)
Long-term debt
Secured Debt	0.0		322.9
Debt Instrument, Face Amount	0.0	$ 322.9
Ten Point Zero Percent Second Lien Notes (Existing Notes) \| Secured Debt
Long-term debt
Total Debt Issuance Costs	$ 0.0		$ 0.0