XML 91 R70.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Additional Information (Details) - USD ($) $ / shares in Units, shares in Millions | Apr. 01, 2017 | Dec. 31, 2017 | Jun. 30, 2017 | Apr. 03, 2017 | Mar. 31, 2017 | Feb. 15, 2017 | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | --- | --- | --- | --- | --- | --- | ---
Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Common stock, shares issued (in shares) |  | 130.7 |  |  |  |  |  |
Assets held-for-sale |  |  |  |  | $ 228,500,000 |  |  |
Write off of mine development costs | $ 89,500,000 |  |  |  |  |  |  |
Write off of prepaid assets | $ 15,000,000 |  |  |  |  |  |  |
Successor |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Common stock, shares outstanding (in shares) | 70.9 | 105.2 |  |  |  |  |  |
Postconfirmation, preferred stock | $ 1,305,400,000 |  |  |  |  |  |  |
Postconfirmation, total stockholders' equity | 3,131,900,000 |  |  |  |  |  |  |
Postconfirmation, long-term debt | 1,853,700,000 |  |  |  |  |  |  |
Debt issuance cost |  | $ 59,400,000 |  |  |  |  | $ 70,800,000 |
Successor | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Final equity value | $ 3,081,000,000 |  |  |  |  |  |  |
Postconfirmation, common stock, share price (in dollars per share) | $ 22.03 |  |  |  |  |  |  |
Common stock, shares issued (in shares) | 70.9 |  |  |  |  |  |  |
Common stock, par value per share (in dollars per share) | $ 0.01 |  |  |  |  |  |  |
Postconfirmation, preferred stock | $ 750,000,000 |  |  |  |  |  |  |
Discount percent of common stock value | 35.00% |  |  |  |  |  |  |
Postconfirmation, common stock, initial share price estimate | $ 25.00 |  |  |  |  |  |  |
Dividends, common stock, paid in kind, guaranteed period | 3 years |  |  |  |  |  |  |
Dividends, common stock, paid in kind, annual stated rate | 8.50% |  |  |  |  |  |  |
Convertible preferred stock, shares issued upon conversion | 46.2 |  |  |  |  |  |  |
Equity ownership percent | 42.00% |  |  |  |  |  |  |
Postconfirmation, total stockholders' equity | $ 3,105,000,000 |  |  |  |  |  |  |
Convertible preferred stock, converted shares, fair value | $ 1,305,400,000 |  |  |  |  |  |  |
Discount rate | 4.10% |  |  |  |  |  | 4.15% |
Remeasurement reduction in pension liabilities | $ 9,200,000 |  |  |  |  |  |  |
Predecessor |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Credit adjusted risk free interest rates |  |  |  |  |  |  |  | 50.83%
2017 Incentive Plan | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Common stock reserved for future issuance | 14.0 |  |  |  |  |  |  |
Incentive plan expiration period | 10 years |  |  |  |  |  |  |
Common stock, shares issued (in shares) |  | 3.5 |  |  |  |  |  |
2017 Incentive Plan | Predecessor | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Common stock reserved for future issuance | 14.0 |  |  |  |  |  |  |
Minimum | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Final equity value | $ 4,200,000,000 |  |  |  |  |  |  |
Discounted cash flow, estimated weighed average cost of capital, percent | 11.00% |  |  |  |  |  |  |
Maximum | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Final equity value | $ 4,900,000,000 |  |  |  |  |  |  |
Discounted cash flow, estimated weighed average cost of capital, percent | 14.50% |  |  |  |  |  |  |
Restricted Stock | 2017 Incentive Plan | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Fair value of stock granted | $ 80,000,000 |  |  |  |  |  |  |
Paid In Kind | Successor | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Convertible preferred stock, shares issued upon conversion | 13.1 |  |  |  |  |  |  |
Successor Credit Agreement | Term Loan | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Principal amount |  |  |  | $ 950,000,000 |  |  |  |
Successor Credit Agreement | Term Loan | Successor |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Principal amount |  |  | $ 450,000,000 |  |  |  |  |
6.00% Senior Secured Notes due March 2022 | Senior Notes | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Principal amount |  |  |  |  |  | $ 500,000,000.0 |  |
6.375% Senior Secured Notes due March 2025 | Senior Notes | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Principal amount |  |  |  |  |  | $ 500,000,000.0 |  |
Senior Secured Term Loan | Term Loan | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Postconfirmation, long-term debt | $ 950,000,000 |  |  |  |  |  |  |
Debt issuance cost | 37,300,000 |  |  |  |  |  |  |
Successor Notes | Senior Notes | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Debt issuance cost | 49,500,000 |  |  |  |  |  |  |
Principal amount | 1,000,000,000.0 |  |  |  |  |  |  |
Coal supply agreements | Successor | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Finite-lived intangible assets, fair value | $ 314,900,000 |  |  |  |  |  |  |
Useful life | 3 years |  |  |  |  |  |  |
Finite-lived intangible assets, fair value, noncurrent | $ 58,700,000 |  |  |  |  |  |  |
Port And Rail Take Or Pay Contracts | Successor | Effect of Plan |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Finite-lived intangible assets, fair value | 32,600,000 |  |  |  |  |  |  |
Liabilities, held-for-sale |  |  |  |  | $ 15,700,000 |  |  |
Finite-lived intangible assets, fair value, noncurrent | $ 83,600,000 |  |  |  |  |  |  |
U.S. Obligations [Member] | Successor |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Credit adjusted risk free interest rates |  | 9.71% |  |  |  |  |  |
U.S. Obligations [Member] | Predecessor |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Credit adjusted risk free interest rates | 9.36% |  |  |  |  |  | 13.45% |
Australian Operations [Member] | Successor |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Credit adjusted risk free interest rates |  | 4.65% |  |  |  |  |  |
Australian Operations [Member] | Predecessor |  |  |  |  |  |  |  |
Fresh-Start Adjustment [Line Items] |  |  |  |  |  |  |  |
Credit adjusted risk free interest rates | 4.36% |  |  |  |  |  | 4.92% |

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