Long-term Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total lease liabilities	$ 29.3	$ 27.3
Less: Debt issuance costs	(34.8)	(42.7)
Long-term Debt and Lease Obligation, Including Current Maturities	1,137.8	1,547.8
Less: Current portion of long-term debt	59.6	44.9
Long-term debt	1,078.2	1,502.9
Senior Notes \| 6.000% Senior Secured Notes due March 2022 (2022 Notes)
Debt Instrument [Line Items]
Long-term debt	$ 23.1	459.0
Stated interest rate	6.00%
Senior Notes \| 6.375% Senior Secured Notes due March 2025 (2025 Notes)
Debt Instrument [Line Items]
Long-term debt	$ 334.9	500.0
Stated interest rate	6.375%
Senior Notes \| 8.500% Senior Secured Notes due 2024 (New Peabody Notes)
Debt Instrument [Line Items]
Stated interest rate	8.50%
Long-term debt	$ 62.6	0.0
Senior Notes \| 10.00% Senior Secured Notes Due 2024 (New Co-Issuer Notes)
Debt Instrument [Line Items]
Stated interest rate	10.00%
Long-term debt	$ 193.9	0.0
Term Loan \| Senior Secured Term Loan due 2025, net of original issue discount
Debt Instrument [Line Items]
Long-term debt	322.8	388.2
Term Loan \| Senior Secured Term Loan Due 2024
Debt Instrument [Line Items]
Long-term debt	206.0	0.0
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt	$ 0.0	$ 216.0

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

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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 noncurrent.

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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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