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Debt (Details) - USD ($) $ in Millions	Sep. 30, 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
Total Debt Issuance Costs	21.6		6.1
Total Debt	3,100.0		5,145.8
Liabilities Subject to Compromise	0.0		(6,397.7)
Debt Instrument, Face Amount	3,583.6
Long-term Debt, Excluding Current Maturities	3,539.5
Long-term Debt	3,055.9		0.0
Debt Issuance Costs	21.6		0.0
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	234.8		0.0
Debt Instrument, Face Amount	321.9	$ 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	473.9		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	1,222.8		0.0
Total Debt	1,382.8
Debt Instrument, Face Amount	1,382.8	1,392.9
2018 Replacement Term Loan
Long-term debt
Total Debt Issuance Costs	0.0		0.0
Secured Debt	327.2		0.0
Total Debt	367.1
Debt Instrument, Face Amount	367.1	369.7
Eleven Point Five Percent First Lien Senior Secured Notes
Long-term debt
Total Debt Issuance Costs	21.6		0.0
Secured Debt	650.0		0.0
Debt Instrument, Face Amount	650.0
Ten Point Zero Percent Second Lien Notes due 2029
Long-term debt
Total Debt Issuance Costs	0.0		0.0
Secured Debt	191.3		0.0
Debt Instrument, Face Amount	366.8	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