Peabody Energy (BTU) 10-Q 8 May 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares shares in Millions	3 Months Ended
	Mar. 31, 2019	May 02, 2019
Entity Information [Line Items]
Entity Registrant Name	PEABODY ENERGY CORP
Entity Central Index Key	0001064728
Document Type	10-Q
Document Period End Date	Mar. 31, 2019
Amendment Flag	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		107

Unaudited Condensed Consolidate

Unaudited Condensed Consolidated Statements of Operations - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenues
Revenues	$ 1,250.6	$ 1,462.7
Costs and expenses
Operating costs and expenses (exclusive of items shown separately below)	948.4	1,057.2
Depreciation, depletion and amortization	172.5	169.6
Asset retirement obligation expenses	13.8	12.3
Selling and administrative expenses	36.7	37
Other operating (income) loss:
Net gain on disposals	(1.5)	(30.6)
Provision for North Goonyella equipment loss	24.7	0
North Goonyella insurance recovery	(125)	0
Income from equity affiliates	(3.5)	(22)
Operating profit	184.5	239.2
Interest expense	35.8	36.3
Interest income	(8.3)	(7.2)
Net periodic benefit costs, excluding service cost	4.9	4.5
Reorganization items, net	0	(12.8)
Income from continuing operations before income taxes	152.1	218.4
Income tax provision	18.8	10.1
Income from continuing operations, net of income taxes	133.3	208.3
Loss from discontinued operations, net of income taxes	(3.4)	(1.3)
Net income	129.9	207
Less: Series A Convertible Preferred Stock dividends	0	102.5
Less: Net income (loss) attributable to noncontrolling interests	5.7	(2.1)
Net income attributable to common stockholders	$ 124.2	$ 106.6
Income from continuing operations:
Basic income per share (in dollars per share)	$ 1.18	$ 0.84
Diluted income per share (in dollars per share)	1.15	0.83
Net income attributable to common stockholders:
Basic income per share (in dollars per share)	1.14	0.83
Diluted income per share (in dollars per share)	$ 1.12	$ 0.82

Unaudited Condensed Consolida_2

Unaudited Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 129.9	$ 207
Amortization of prior service credit included in net income	(2.2)	0
Postretirement plans and workers’ compensation obligations	(2.2)	0
Foreign currency translation adjustment	0.1	(0.8)
Other comprehensive loss, net of income taxes	(2.1)	(0.8)
Comprehensive income	127.8	206.2
Less: Series A Convertible Preferred Stock dividends	0	102.5
Less: Net income (loss) attributable to noncontrolling interests	5.7	(2.1)
Comprehensive income attributable to common stockholders	$ 122.1	$ 105.8

Unaudited Condensed Consolida_3

Unaudited Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Postretirement plans and workers' compensation obligations, tax provision	$ 0	$ 0

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Current assets
Cash and cash equivalents	$ 798.1	$ 981.9
Accounts receivable, net of allowance for doubtful accounts of $4.4 at March 31, 2019 and December 31, 2018	554.6	450.4
Inventories	268.5	280.2
Other current assets	239.5	243.1
Total current assets	1,860.7	1,955.6
Property, plant, equipment and mine development, net	5,069.5	5,207
Operating lease right-of-use assets	97	0
Investments and other assets	211.8	212.6
Deferred income taxes	48.5	48.5
Total assets	7,287.5	7,423.7
Current liabilities
Current portion of long-term debt	34.8	36.5
Accounts payable and accrued expenses	1,014.4	1,022
Total current liabilities	1,049.2	1,058.5
Long-term debt, less current portion	1,326.9	1,330.5
Deferred income taxes	9.7	9.7
Asset retirement obligations	691.8	686.4
Accrued postretirement benefit costs	543.7	547.7
Operating lease liabilities, less current portion	58.2	0
Other noncurrent liabilities	345.9	339.3
Total liabilities	4,025.4	3,972.1
Stockholders’ equity
Peabody Energy Corporation stockholders’ equity	3,214.7	3,395.6
Noncontrolling interests	47.4	56
Total stockholders’ equity	3,262.1	3,451.6
Total liabilities and stockholders’ equity	7,287.5	7,423.7
Preferred Stock
Stockholders’ equity
Total stockholders’ equity	0	0
Common Stock
Stockholders’ equity
Total stockholders’ equity	1.4	1.4
Additional Paid-in Capital
Stockholders’ equity
Additional paid-in capital	3,322.3	3,304.7
Total stockholders’ equity	3,322.3	3,304.7
Treasury Stock
Stockholders’ equity
Treasury stock, at cost	(1,125.3)	(1,025.1)
Total stockholders’ equity	(1,125.3)	(1,025.1)
Retained earnings
Stockholders’ equity
Retained earnings	978.3	1,074.5
Total stockholders’ equity	978.3	1,074.5
Total Accumulated Other Comprehensive Income
Stockholders’ equity
Accumulated other comprehensive income	38	40.1
Total stockholders’ equity	38	40.1
Preferred Stock
Stockholders’ equity
Preferred Stock	0	0
Series Common Stock
Stockholders’ equity
Common Stock	0	0
Common Stock | Common Stock
Stockholders’ equity
Common Stock	$ 1.4	$ 1.4

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Millions, $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Current assets
Allowance for doubtful accounts	$ 4.4	$ 4.4
Stockholders' equity
Treasury stock, shares (in shares)	30.4	27.3
Convertible Preferred Stock
Stockholders' equity
Preferred stock, par value per share (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	0	0
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Preferred Stock
Stockholders' equity
Preferred stock, par value per share (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	100	100
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Series Common Stock
Stockholders' equity
Common stock, par value per share (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	50	50
Common stock, shares issued (in shares)	0	0
Common stock, shares outstanding (in shares)	0	0
Common Stock
Stockholders' equity
Common stock, par value per share (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	450	450
Common stock, shares issued (in shares)	137.9	137.7
Common stock, shares outstanding (in shares)	107.5	110.4

Unaudited Condensed Consolida_4

Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Mar. 31, 2019	Dec. 31, 2018
Cash Flows From Operating Activities
Net income	$ 129.9	$ 207
Loss from discontinued operations, net of income taxes	3.4	1.3
Income from continuing operations, net of income taxes	133.3	208.3
Adjustments to reconcile income from continuing operations, net of income taxes to net cash provided by operating activities:
Depreciation, depletion and amortization	172.5	169.6
Noncash interest expense, net	5.5	3.1
Deferred income taxes	0	0.7
Noncash share-based compensation	11.6	8.1
Net gain on disposals	(1.5)	(30.6)
Income from equity affiliates	(3.5)	(22)
Provision for North Goonyella equipment loss	24.7	0	$ 66.4
North Goonyella insurance recovery	(116.9)	0
Foreign currency option contracts	1.1	2
Noncash reorganization items, net	0	(12.8)
Changes in current assets and liabilities:
Accounts receivable	5.5	117.1
Inventories	11.1	25.2
Other current assets	(3.1)	(34.3)
Accounts payable and accrued expenses	(30.6)	(45.4)
Collateral arrangements	0	214
Asset retirement obligations	5.5	7
Workers’ compensation obligations	0.8	0.3
Postretirement benefit obligations	(6.2)	(2.6)
Pension obligations	1	(32.3)
(Payments for) proceeds from other operating activities	(10)	5.3
Net cash provided by continuing operations	200.8	580.7
Net cash used in discontinued operations	(3.2)	(1)
Net cash provided by operating activities	197.6	579.7
Cash Flows From Investing Activities
Additions to property, plant, equipment and mine development	(35.8)	(53.7)
Changes in accrued expenses related to capital expenditures	(3.8)	(4.9)
Federal coal lease expenditures	0	(0.5)
Proceeds from disposal of assets, net of receivables	11	23
Amount attributable to acquisition of Shoal Creek Mine	(2.4)	0
Contributions to joint ventures	(118.4)	(123.5)
Distributions from joint ventures	110.9	120.7
Advances to related parties	(1.5)	(2)
Cash receipts from Middlemount Coal Pty Ltd	1.1	35.8
(Payments for) proceeds from other investing activities	0.8	(1.3)
Net cash used in investing activities	(38.1)	(6.4)
Cash Flows From Financing Activities
Repayments of long-term debt	(8.3)	(8.2)
Common stock repurchases	(98.8)	(175.5)
Repurchase of employee common stock relinquished for tax withholding	(1.4)	0
Dividends paid	(214.4)	(15)
Distributions to noncontrolling interests	(14.3)	(6.6)
(Payments for) proceeds from other financing activities	(0.1)	0.2
Net cash used in financing activities	(337.3)	(205.1)
Net change in cash, cash equivalents and restricted cash	(177.8)	368.2
Cash, cash equivalents and restricted cash at beginning of period	1,017.4	1,070.2	1,070.2
Cash, cash equivalents and restricted cash at end of period	839.6	1,438.4	1,017.4
Reconciliation of cash, cash equivalents and restricted cash
Cash and cash equivalents				$ 798.1	$ 981.9
Restricted cash included in “Investments and other assets”				41.5	35.5
Cash, cash equivalents and restricted cash	$ 1,017.4	$ 1,070.2	$ 1,070.2	$ 839.6	$ 1,017.4

Unaudited Condensed Consolida_5

Unaudited Condensed Consolidated Statement of Changes in Stockholders' Equity - USD ($) $ in Millions	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Treasury Stock	Retained earnings	Total Accumulated Other Comprehensive Income	Noncontrolling Interest
Balance, beginning of period at Dec. 31, 2017		$ 576	$ 1	$ 2,590.3	$ (175.9)	$ 613.6	$ 1.4	$ 49.4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Impact of adoption of Accounting Standards Update 2014-09						(22.5)
Net income	$ 106.6					209.1
Dividends declared				0.4		(15.4)
Series A Convertible Preferred Stock conversions		(576)	0.4	678.1		(102.5)
Share-based compensation for equity-classified awards				8.1
Common stock repurchases	175.5				(175.5)
Repurchase of employee common stock relinquished for tax withholding	0				0
Net income (loss)	207							(2.1)
Distributions to noncontrolling interests								(6.6)
Postretirement plans and workers' compensation obligations (net of respective tax provision of $0.0 and $0.0)	0						0
Foreign currency translation adjustment	(0.8)						(0.8)
Balance, end of period at Mar. 31, 2018	3,650.5	0	1.4	3,276.9	(351.4)	682.3	0.6	40.7
Balance, beginning of period at Dec. 31, 2018	3,451.6	0	1.4	3,304.7	(1,025.1)	1,074.5	40.1	56
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Impact of adoption of Accounting Standards Update 2014-09						0
Net income	124.2					124.2
Dividends declared				6		(220.4)
Series A Convertible Preferred Stock conversions		0	0	0		0
Share-based compensation for equity-classified awards				11.6
Common stock repurchases	98.8				(98.8)
Repurchase of employee common stock relinquished for tax withholding	1.4				(1.4)
Net income (loss)	129.9							5.7
Distributions to noncontrolling interests								(14.3)
Postretirement plans and workers' compensation obligations (net of respective tax provision of $0.0 and $0.0)	2.2						(2.2)
Foreign currency translation adjustment	0.1						0.1
Balance, end of period at Mar. 31, 2019	$ 3,262.1	$ 0	$ 1.4	$ 3,322.3	$ (1,125.3)	$ 978.3	$ 38	$ 47.4

Unaudited Condensed Consolida_6

Unaudited Condensed Consolidated Statement of Changes in Stockholders' Equity Unaudited Condensed Consolidated Statement of Changes in Stockholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Retained earnings
Dividends declared per share	$ 1.980	$ 0.115

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The condensed consolidated financial statements include the accounts of Peabody Energy Corporation (PEC) and its consolidated subsidiaries and affiliates (along with PEC, the Company or Peabody). Interests in subsidiaries controlled by the Company are consolidated with any outside stockholder interests reflected as noncontrolling interests, except when the Company has an undivided interest in an unincorporated joint venture. In those cases, the Company includes its proportionate share in the assets, liabilities, revenues and expenses of the jointly controlled entities within each applicable line item of the unaudited condensed consolidated financial statements. All intercompany transactions, profits and balances have been eliminated in consolidation. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (U.S. GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements and should be read in conjunction with the consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 . In the opinion of management, these financial statements reflect all normal, recurring adjustments necessary for a fair presentation. Balance sheet information presented herein as of December 31, 2018 has been derived from the Company’s audited consolidated balance sheet at that date. The Company’s results of operations for the three months ended March 31, 2019 are not necessarily indicative of the results that may be expected for future quarters or for the year ending December 31, 2019 . The Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) 852, “Reorganizations”, requires that financial statements distinguish transactions and events that are directly associated with a reorganization from the ongoing operations of the business. Accordingly, certain revenues, expenses, realized gains and losses and provisions for losses that were realized or incurred during the bankruptcy proceedings from which the Company emerged on April 3, 2017 were recorded in “Reorganization items, net” in the unaudited condensed consolidated statements of operations. “Reorganization items, net” for the three months ended March 31, 2018 consisted of settlement gains of $12.8 million related to certain unsecured claims.

Newly Adopted Accounting Standa

Newly Adopted Accounting Standards and Accounting Standards Not Yet Implemented	3 Months Ended
	Mar. 31, 2019
Newly Adopted Accounting Standards and Accounting Standards Not Yet Implemented [Abstract]
New Accounting Pronouncements and Changes in Accounting Principles [Text Block]	Newly Adopted Accounting Standards and Accounting Standards Not Yet Implemented Newly Adopted Accounting Standards Leases. In February 2016, the FASB issued Accounting Standards Update (ASU) 2016-02, “Leases (Topic 842),” to increase transparency and comparability among organizations by requiring the recognition of right-of-use (ROU) assets and lease liabilities on the balance sheet for leases with lease terms of more than 12 months. Most prominent among the changes in the standard is the recognition of ROU assets and lease liabilities by lessees for those leases classified as operating leases. The FASB has continued to clarify this guidance through the issuance of additional updates to ASU 2016-02. On January 1, 2019, the Company adopted ASU 2016-02 using the modified transition approach and elected the package of practical expedients offered under ASU 2016-02, as updated, that allows it to forgo reassessment of lease classification for leases that have already commenced. The Company also elected the practical expedients to adopt ASU 2016-02 without restating comparative prior period financial information, to not recognize ROU assets and lease liabilities for operating leases with shorter than 12 month terms and to include both lease and non-lease components within lease payments. The Company has implemented the systems functionality and internal control processes necessary to comply with the new reporting requirements of ASU 2016-02. The Company recognized the cumulative effect of initially applying ASU 2016-02 as an adjustment on January 1, 2019 and comparative information presented herein has not been restated. ASU 2016-02 had a material impact on the Company's consolidated balance sheet but did not have a material impact on its results of operations or its cash flows. The most significant impact was the recognition of ROU assets and lease liabilities for operating leases upon adoption, as set forth in the table below. The Company's accounting for finance leases remained unchanged. Adoption of ASU 2016-02 January 1, 2019 (Dollars in millions) ASSETS Operating lease right-of-use assets $ 109.3 Total assets $ 109.3 LIABILITIES Accounts payable and accrued expenses $ 41.8 Total current liabilities 41.8 Operating lease liabilities, less current portion 67.5 Total liabilities $ 109.3 ASU 2016-02 also requires entities to disclose certain qualitative and quantitative information regarding the amount, timing, and uncertainty of cash flows arising from leases. Such disclosures are included in Note 11. “Leases.” Leases to explore for or use minerals, oil, natural gas and similar non-regenerative resources, including the intangible rights to explore for those natural resources and rights to use the land in which those natural resources are contained are excluded from the scope of ASU 2016-02. As such, the adoption of ASU 2016-02 did not impact the accounting for the coal reserve leases under which the Company mines a substantial amount of its coal production. Such leases typically require royalties to be paid as the coal is mined and sometimes require minimum annual royalties to be paid regardless of the amount of coal mined during the year. Leases - Land Easements. In January 2018, the FASB issued ASU 2018-01 to provide an optional transition practical expedient to not evaluate under Topic 842 existing or expired land easements that were not previously accounted for as leases under prior leasing guidance. On January 1, 2019, the Company adopted the expedient to evaluate new or modified land easements under Topic 842, and it did not have a material impact on the Company’s results of operations, financial condition, cash flows or financial statement presentation. Accounting Standards Not Yet Implemented Financial Instruments - Credit Losses. In June 2016, the FASB issued ASU 2016-13 related to the measurement of credit losses on financial instruments. The pronouncement replaces the incurred loss methodology to record credit losses with a methodology that reflects the expected credit losses for financial assets not accounted for at fair value with gains and losses recognized through net income. This standard is effective for fiscal years beginning after December 15, 2019 (January 1, 2020 for the Company) and interim periods therein, with early adoption permitted for fiscal years, and interim periods therein, beginning after December 15, 2018. The Company is in the process of evaluating the update and expects to adopt ASU 2016-13 as of January 1, 2020 with no material impact to the Company’s results of operations, financial condition, cash flows or financial statement presentation. Fair Value Measurement. In August 2018, the FASB issued ASU 2018-13, which amended the fair value measurement guidance by removing and modifying certain disclosure requirements, while also adding new disclosure requirements. The amendments on changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial fiscal year of adoption. All other amendments should be applied retrospectively to all periods presented upon their effective date. The amendments are effective for all companies for fiscal years, and interim periods within those years, beginning after December 15, 2019. Early adoption is permitted for all amendments. Further, a company may elect to early adopt the removal or modification of disclosures immediately and delay adoption of the new disclosure requirements until the effective date. The Company plans to adopt all disclosure requirements effective January 1, 2020. Compensation - Retirement Benefits. In August 2018, the FASB issued ASU 2018-14 to add, remove and clarify disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans. ASU 2018-14 is effective for fiscal years ending after December 15, 2020 for public companies and early adoption is permitted. The Company plans to adopt the disclosure requirements effective January 1, 2021.

Acquisition of Shoal Creek Mine

Acquisition of Shoal Creek Mine	3 Months Ended
	Mar. 31, 2019
Acquisition of Shoal Creek Mine [Abstract]
Acquisition of Shoal Creek Mine [Text Block]	Acquisition of Shoal Creek Mine On December 3, 2018, the Company completed the acquisition of the Shoal Creek metallurgical coal mine, preparation plant and supporting assets located in Alabama (Shoal Creek Mine) for a purchase price of $387.4 million . In January 2019, the Company agreed to pay an additional $2.4 million to settle a working capital adjustment. The purchase price was funded with available cash on hand and reflected customary purchase price adjustments. The acquisition expands the Company’s seaborne metallurgical mining platform. The acquisition excluded all liabilities other than reclamation and the Company is not responsible for other liabilities arising out of or relating to the operation of the Shoal Creek Mine prior to the acquisition date, including with respect to employee benefit plans and post-employment benefits. In connection with completing the acquisition, a new collective bargaining agreement was reached with the union-represented workforce that eliminates participation in the multi-employer pension plan and replaces it with a 401(k) retirement plan. The preliminary purchase accounting allocations have been recorded in the accompanying unaudited condensed consolidated financial statements as of, and for the period subsequent to the acquisition date. The following table summarizes the preliminary estimated fair values of assets acquired and liabilities assumed that were recognized at the acquisition and control date (in millions): Inventories $ 39.7 Property, plant, equipment and mine development 364.7 Current liabilities (4.1 ) Asset retirement obligations (10.5 ) Total purchase price $ 389.8 Determining the fair value of assets acquired and liabilities assumed required judgment and the utilization of independent valuation experts, and included the use of significant estimates and assumptions, including assumptions with respect to future cash inflows and outflows, discount rates and asset lives, among other items. Due to the unobservable inputs to the valuation, the fair value would be considered Level 3 in the fair value hierarchy. The changes to the purchase price allocation during the three months ended March 31, 2019 were all contained within the amounts allocated to property, plant, equipment and mine development. Those changes did not have an impact on the amount of depletion, depreciation or amortization that would have been recorded during the year ended December 31, 2018 had the update purchase price allocation been known at that time. The Company is evaluating the mine plan, assessing the equipment and inventories, and reviewing coal reserve studies on the Shoal Creek Mine, the outcome of which will determine the fair value allocated to the asset retirement obligation, coal reserve assets and equipment. The valuation of the net assets acquired is expected to be finalized once those assessments and third-party valuation appraisals are completed. In connection with the acquisition, the Company recorded a contract based intangible liability of $3.5 million to reflect the fair value of a coal supply agreement. The liability was amortized to income in January 2019 and the related contract was renegotiated on market terms. The results of Shoal Creek Mine for the three months ended March 31, 2019 are included in the unaudited condensed consolidated statement of operations and are reported in the Seaborne Metallurgical Mining segment. The following unaudited pro forma financial information presents the estimated combined results of operations of the Company and Shoal Creek Mine, on a pro forma basis, as though the operations of the Shoal Creek Mine had been combined with the Company’s operations as of January 1, 2018. The unaudited pro forma financial information does not necessarily reflect the results of operations that would have occurred had the operations of the Company and Shoal Creek Mine been combined during those periods or that may be attained in the future. Three Months Ended March, 31, 2018 (Dollars in millions, except per share data) Revenues $ 1,567.7 Income from continuing operations, net of income taxes 251.2 Basic earnings per share from continuing operations $ 1.17 Diluted earnings per share from continuing operations $ 1.15 The pro forma income from continuing operations, net of income taxes includes adjustments to operating costs to reflect the additional expense for the estimated impact of the fair value adjustment for coal inventory, a reduction in postretirement benefit costs resulting from the new collective bargaining agreement described above, and the estimated impact on depreciation, depletion and amortization for the fair value adjustment for property, plant and equipment (including coal reserve assets). On a pro forma basis, the acquisition would have had no impact on taxable income due to the Company’s federal net operating losses.

Revenues

Revenues	3 Months Ended
	Mar. 31, 2019
Revenue Recognition [Abstract]
Revenues [Text Block]	Revenue Recognition The Company accounts for revenue in accordance with ASC Topic 606, “Revenue from Contracts with Customers” (ASC 606), which the Company adopted on January 1, 2018, using the modified retrospective approach. Refer to Note 1. “Summary of Significant Accounting Policies” in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018, for the Company’s policies regarding “Revenues” and “Accounts receivable, net.” Disaggregation of Revenues Revenue by product type and market is set forth in the following tables. With respect to its seaborne mining segments, the Company classifies as “Export” certain revenue from domestically-delivered coal under contracts in which the price is derived on a basis similar to export contracts. Three Months Ended March 31, 2019 Seaborne Thermal Mining Seaborne Metallurgical Mining Powder River Basin Mining Midwestern U.S. Mining Western U.S. Mining Corporate and Other (1) Consolidated (Dollars in millions) Thermal coal Domestic $ 38.4 $ — $ 287.3 $ 179.0 $ 142.7 $ — $ 647.4 Export 211.9 — — — 7.0 — 218.9 Total thermal 250.3 — 287.3 179.0 149.7 — 866.3 Metallurgical coal Export — 323.7 — — — — 323.7 Total metallurgical — 323.7 — — — — 323.7 Other 0.7 0.8 — 0.1 6.0 53.0 60.6 Revenues $ 251.0 $ 324.5 $ 287.3 $ 179.1 $ 155.7 $ 53.0 $ 1,250.6 Three Months Ended March 31, 2018 Seaborne Thermal Mining Seaborne Metallurgical Mining Powder River Basin Mining Midwestern U.S. Mining Western U.S. Mining Corporate and Other (1) Consolidated (Dollars in millions) Thermal coal Domestic $ 36.1 $ — $ 389.2 $ 200.9 $ 130.3 $ — $ 756.5 Export 164.9 — — 0.7 8.0 — 173.6 Total thermal 201.0 — 389.2 201.6 138.3 — 930.1 Metallurgical coal Export — 465.3 — — — — 465.3 Total metallurgical — 465.3 — — — — 465.3 Other 0.4 0.9 0.1 0.1 5.4 60.4 67.3 Revenues $ 201.4 $ 466.2 $ 389.3 $ 201.7 $ 143.7 $ 60.4 $ 1,462.7 Revenue by contract duration was as follows: Three Months Ended March 31, 2019 Seaborne Thermal Mining Seaborne Metallurgical Mining Powder River Basin Mining Midwestern U.S. Mining Western U.S. Mining Corporate and Other (1) Consolidated (Dollars in millions) One year or longer $ 171.1 $ 232.8 $ 280.1 $ 167.8 $ 146.0 $ — $ 997.8 Less than one year 79.2 90.9 7.2 11.2 3.7 — 192.2 Other (2) 0.7 0.8 — 0.1 6.0 53.0 60.6 Revenues $ 251.0 $ 324.5 $ 287.3 $ 179.1 $ 155.7 $ 53.0 $ 1,250.6 Three Months Ended March 31, 2018 Seaborne Thermal Mining Seaborne Metallurgical Mining Powder River Basin Mining Midwestern U.S. Mining Western U.S. Mining Corporate and Other (1) Consolidated (Dollars in millions) One year or longer $ 177.3 $ 397.5 $ 343.4 $ 187.6 $ 127.3 $ — $ 1,233.1 Less than one year 23.7 67.8 45.8 14.0 11.0 — 162.3 Other (2) 0.4 0.9 0.1 0.1 5.4 60.4 67.3 Revenues $ 201.4 $ 466.2 $ 389.3 $ 201.7 $ 143.7 $ 60.4 $ 1,462.7 (1) Corporate and Other revenue includes realized and unrealized gains and losses related to mark-to-market activity from economic hedge activities intended to hedge future coal sales. Refer to Note 8. “Derivatives and Fair Value Measurements” for additional information regarding the economic hedge activities. (2) Other includes revenues from arrangements such as customer contract-related payments, royalties related to coal lease agreements, sales agency commissions, farm income and property and facility rentals, for which contract duration is not meaningful. Committed Revenue from Contracts with Customers The Company expects to recognize revenue subsequent to March 31, 2019 of approximately $5.0 billion related to contracts with customers in which volumes and prices per ton were fixed or reasonably estimable at March 31, 2019 . Approximately 47% of such amount is expected to be recognized over the next twelve months and the remainder thereafter. Actual revenue related to such contracts may differ materially for various reasons, including price adjustment features for coal quality and cost escalations, volume optionality provisions and potential force majeure events. This estimate of future revenue does not include any revenue related to contracts with variable prices per ton that cannot be reasonably estimated, such as the majority of seaborne metallurgical and seaborne thermal coal contracts where pricing is negotiated or settled quarterly or annually. Accounts Receivable “Accounts receivable, net” at March 31, 2019 and December 31, 2018 consisted of the following: March 31, 2019 December 31, 2018 (Dollars in millions) Trade receivables, net $ 366.6 $ 345.5 Miscellaneous receivables, net 188.0 104.9 Accounts receivable, net $ 554.6 $ 450.4 Trade receivables, net presented above have been shown net of reserves of $0.1 million as of both March 31, 2019 and December 31, 2018 . Miscellaneous receivables, net presented above have been shown net of reserves of $4.3 million as of both March 31, 2019 and December 31, 2018 . Included in “Operating costs and expenses” in the unaudited condensed consolidated statements of operations was a charge for doubtful trade receivables of $0.2 million for the three months ended March 31, 2018 . No charges for doubtful accounts were recognized during the three months ended March 31, 2019 . The Company also records long-term customer receivables related to the reimbursement of certain post-mining costs which are included within “Investments and other assets” in the accompanying condensed consolidated balance sheets. The balance of such receivables was $11.3 million and $11.1 million as of March 31, 2019 and December 31, 2018 , respectively. In connection with the adoption of ASC 606, the Company records a portion of the consideration received as “Interest income” in the accompanying unaudited condensed consolidated statements of operations, due to the embedded financing element within the related contract. Interest income related to these arrangements amounted to $2.7 million and $2.1 million during the three months ended March 31, 2019 and 2018 , respectively.

Discontinued Operations

Discontinued Operations	3 Months Ended
	Mar. 31, 2019
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	Discontinued Operations Discontinued operations include certain former Seaborne Thermal Mining and Midwestern U.S. Mining segment assets that have ceased production and other previously divested legacy operations, including Patriot Coal Corporation and certain of its wholly-owned subsidiaries (Patriot). Summarized Results of Discontinued Operations Results from discontinued operations were as follows during the periods presented below: Three Months Ended March 31, 2019 2018 (Dollars in millions) Loss from discontinued operations, net of income taxes $ (3.4 ) $ (1.3 ) Liabilities of Discontinued Operations Liabilities classified as discontinued operations included in the Company’s condensed consolidated balance sheets were as follows: March 31, 2019 December 31, 2018 (Dollars in millions) Liabilities: Accounts payable and accrued expenses $ 54.0 $ 54.0 Other noncurrent liabilities 141.3 141.0 Total liabilities classified as discontinued operations $ 195.3 $ 195.0 Patriot-Related Matters A significant portion of the liabilities in the table above relate to Patriot. In 2012, Patriot filed voluntary petitions for relief under the Bankruptcy Code. In 2013, the Company entered into a definitive settlement agreement (2013 Agreement) with Patriot and the United Mine Workers of America (UMWA), on behalf of itself, its represented Patriot employees and its represented Patriot retirees, to resolve all then-disputed issues related to Patriot’s bankruptcy. In May 2015, Patriot again filed voluntary petitions for relief under Chapter 11 of Title 11 of the U.S. Code (the Bankruptcy Code) in the Eastern District of Virginia and subsequently initiated a process to sell some or all of its assets to qualified bidders. On October 9, 2015, Patriot’s bankruptcy court entered an order confirming Patriot’s plan of reorganization, which provided, among other things, for the sale of substantially all of Patriot’s assets to two different buyers. Black Lung Occupational Disease Liabilities. Patriot had federal and state black lung occupational disease liabilities related to workers employed in periods prior to Patriot’s spin-off from the Company in 2007. Upon spin-off, Patriot indemnified the Company against any claim relating to these liabilities, which amounted to approximately $150 million at that time. The indemnification included any claim made by the U.S. Department of Labor (DOL) against the Company with respect to these obligations as a potentially liable operator under the Federal Coal Mine Health and Safety Act of 1969. The 2013 Agreement included Patriot’s affirmance of indemnities provided in the spin-off agreements, including the indemnity relating to such black lung liabilities; however, Patriot rejected this indemnity in its May 2015 bankruptcy. By statute, the Company had secondary liability for the black lung liabilities related to Patriot’s workers employed by former subsidiaries of the Company. The Company’s accounting for the black lung liabilities related to Patriot is based on an interpretation of applicable statutes. Management believes that inconsistencies exist among the applicable statutes, regulations promulgated under those statutes and the DOL’s interpretative guidance. The Company has sought clarification from the DOL regarding these inconsistencies and the accounting for these liabilities could be reduced in the future depending on the DOL’s responses. Whether the Company will ultimately be required to fund certain of those obligations in the future as a result of Patriot’s May 2015 bankruptcy remains uncertain. The amount of the liability, which was determined on an actuarial basis based on the best information available to the Company, was $103.1 million and $102.7 million at March 31, 2019 and December 31, 2018 , respectively. While the Company has recorded a liability, it intends to review each claim on a case-by-case basis and contest liability estimates as appropriate. The amount of the Company’s recorded liability reflects only Patriot workers employed by former subsidiaries of the Company that are presently retired, disabled or otherwise not actively employed. The Company cannot reliably estimate the potential liabilities for Patriot’s workers employed by former subsidiaries of the Company that are presently active in the workforce because of the potential for such workers to continue to work for another coal operator that is a going concern. Combined Benefit Fund (Combined Fund). The Combined Fund was created by the Coal Act in 1992 as a multi-employer plan to provide health care benefits to a closed group of retirees who last worked prior to 1976, as well as orphaned beneficiaries of bankrupt companies who were receiving benefits as orphans prior to the passage of the Coal Act. No new retirees will be added to this group, which includes retirees formerly employed by certain Patriot subsidiaries and their predecessors. Former employers are required to contribute to the Combined Fund according to a formula. Under the terms of the Patriot spin-off, Patriot was primarily liable to the Combined Fund for the approximately $40.0 million of its subsidiaries’ obligations at that time. Once Patriot ceased meeting its obligations, the Company was held responsible for these costs and, as a result, recorded “Loss from discontinued operations, net of income taxes” charges of $0.2 million during the three months ended March 31, 2019 and 2018. The Company made payments into the fund of $0.5 million and $0.6 million during the three months ended March 31, 2019 and 2018, respectively, and estimates that the annual cash cost to fund these potential Combined Fund liabilities will range between $1 million and $2 million in the near-term, with those premiums expected to decline over time because the fund is closed to new participants. The liability related to the fund was $16.0 million and $16.4 million at March 31, 2019 and December 31, 2018 , respectively. UMWA 1974 Pension Plan (UMWA Plan) Litigation. On July 16, 2015, a lawsuit was filed by the UMWA Plan, the UMWA 1974 Pension Trust (Trust) and the Trustees of the UMWA Plan and Trust (Trustees) in the United States District Court for the District of Columbia, against PEC, Peabody Holding Company, LLC, a subsidiary of the Company, and Arch Coal, Inc. The plaintiffs sought, pursuant to the Employee Retirement Income Security Act of 1974 (ERISA) and the Multiemployer Pension Plan Amendments Act of 1980, a declaratory judgment that the defendants were obligated to arbitrate any opposition to the Trustees’ determination that the defendants have statutory withdrawal liability as a result of the 2015 Patriot bankruptcy. After a legal and arbitration process and with the approval of the U.S. Bankruptcy Court for the Eastern District of Missouri (Bankruptcy Court), on January 25, 2017, the UMWA Plan and the Company agreed to a settlement of the claim which entitled the UMWA Plan to $75 million to be paid by the Company in increments through 2021. The balance of the liability, on a discounted basis, was $37.8 million and $36.7 million at March 31, 2019 and December 31, 2018 , respectively.

Inventories

Inventories	3 Months Ended
	Mar. 31, 2019
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories as of March 31, 2019 and December 31, 2018 consisted of the following: March 31, 2019 December 31, 2018 (Dollars in millions) Materials and supplies $ 118.9 $ 118.1 Raw coal 50.0 53.6 Saleable coal 99.6 108.5 Total $ 268.5 $ 280.2 Materials and supplies inventories presented above have been shown net of reserves of $1.1 million and $0.2 million as of March 31, 2019 and December 31, 2018 , respectively.

Equity Method Investments

Equity Method Investments	3 Months Ended
	Mar. 31, 2019
Financing Receivables [Abstract]
Equity Method Investments	Equity Method Investments The Company had total equity method investments of $48.4 million and $45.9 million reflected in “Investments and other assets” in the condensed consolidated balance sheets as of March 31, 2019 and December 31, 2018 , respectively, related to Middlemount Coal Pty Ltd (Middlemount). Included in “Income from equity affiliates” in the unaudited condensed consolidated statements of operations was $3.8 million and $22.2 million related to Middlemount for the three months ended March 31, 2019 and 2018 , respectively. Middlemount’s standalone results include (on a 50% attributable basis): Three Months Ended March 31, 2019 2018 (Dollars in millions) Depreciation, depletion and amortization and asset retirement obligation expenses $ 3.6 $ 3.9 Net interest expense 2.2 3.6 Income tax provision 1.7 5.1 The Company received cash payments from Middlemount of $1.1 million and $35.8 million during the three months ended March 31, 2019 and 2018 , respectively.

Derivatives and Fair Value Meas

Derivatives and Fair Value Measurements	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Derivatives and Fair Value [Text Block]	Derivatives and Fair Value Measurements Derivatives Corporate Risk Management Activities From time to time, the Company may utilize various types of derivative instruments to manage its exposure to risks in the normal course of business, including (1) foreign currency exchange rate risk and the variability of cash flows associated with forecasted Australian dollar expenditures made in its Australian mining platform, (2) price risk of fluctuating coal prices related to forecasted sales or purchases of coal, or changes in the fair value of a fixed price physical sales contract, (3) price risk and the variability of cash flows related to forecasted diesel fuel purchased for use in its operations, and (4) interest rate risk on long-term debt. These risk management activities are actively monitored for compliance with the Company’s risk management policies. As of March 31, 2019 , the Company had currency options outstanding with an aggregate notional amount of $975.0 million Australian dollars to hedge currency risk associated with anticipated Australian dollar expenditures during the remainder of 2019. The instruments are quarterly average rate options whereby the Company is entitled to receive payment on the notional amount should the quarterly average Australian dollar-to-U.S. dollar exchange rate exceed amounts ranging from $0.76 to $0.77 over the remainder of 2019. As of March 31, 2019 , the Company held coal-related financial contracts related to a portion of its forecasted sales for an aggregate notional volume of 3.7 million tonnes. Such financial contracts include futures, forwards and options. Of the aggregate notional volume, 2.2 million tonnes will settle in 2019 and the remainder will settle in 2020. The Company had no diesel fuel or interest rate derivatives in place as of March 31, 2019 . Coal Trading Activities On a limited basis, the Company engages in the direct and brokered trading of coal and freight-related contracts (coal trading). Except those contracts for which the Company has elected to apply a normal purchases and normal sales exception, all derivative coal trading contracts are accounted for at fair value. Coal brokering is conducted both as principal and agent in support of various coal production-related activities that may involve coal produced from the Company’s mines, coal sourcing arrangements with third-party mining companies or offtake agreements with other coal producers. The Company also provides transportation-related services, which involve both financial derivative contracts and physical contracts. Collectively, coal and freight-related hedging activities include both economic hedging and, from time to time, cash flow hedging in support of the Company’s coal trading strategy. Revenues from such transactions include realized and unrealized gains and losses on derivative instruments, including those that arise from coal deliveries related to contracts accounted for on an accrual basis under the normal purchases and normal sales exception. Offsetting and Balance Sheet Presentation The Company has master netting agreements with certain of its counterparties which allow for the settlement of contracts in an asset position with contracts in a liability position in the event of default or termination. Such netting arrangements reduce the Company’s credit exposure related to these counterparties. For classification purposes, the Company records the net fair value of all the positions with a given counterparty as a net asset or liability in the condensed consolidated balance sheets. The Company’s coal trading assets and liabilities include financial instruments cleared through various exchanges, which involve the daily net settlement of open positions. The Company must post cash collateral in the form of initial margin, in addition to variation margin, on exchange-cleared positions that are in a net liability position and receives variation margin when in a net asset position. The Company also transacts in coal trading financial swaps and options through over-the-counter (OTC) markets with financial institutions and other non-financial trading entities under International Swaps and Derivatives Association (ISDA) Master Agreements, which contain symmetrical default provisions. Certain of the Company’s coal trading agreements with OTC counterparties also contain credit support provisions that may periodically require the Company to post, or entitle the Company to receive, variation margin. Physical coal and freight-related purchase and sale contracts included in the Company’s coal trading assets and liabilities are executed pursuant to master purchase and sale agreements that also contain symmetrical default provisions and allow for the netting and setoff of receivables and payables that arise during the same time period. The Company offsets its coal trading asset and liability derivative positions, and variation margin related to those positions, on a counterparty-by-counterparty basis in the condensed consolidated balance sheets. The fair value of derivatives reflected in the accompanying condensed consolidated balance sheets are set forth in the table below. March 31, 2019 December 31, 2018 Asset Derivative Liability Derivative Asset Derivative Liability Derivative (Dollars in millions) Foreign currency option contracts $ 1.3 $ — $ 1.2 $ — Coal contracts related to forecasted sales 23.0 (7.9 ) 6.6 (23.1 ) Coal trading contracts 144.9 (137.7 ) 59.7 (64.4 ) Total derivatives 169.2 (145.6 ) 67.5 (87.5 ) Effect of counterparty netting (145.5 ) 145.5 (64.5 ) 64.5 Variation margin (held) posted (18.2 ) — — 21.8 Net derivatives and margin as classified in the balance sheets $ 5.5 $ (0.1 ) $ 3.0 $ (1.2 ) The net amounts of asset derivatives are included in “Other current assets” and the net amount of liability derivatives, net of margin, are included in “Accounts payable and accrued expenses” in the accompanying condensed consolidated balance sheets. Effects of Derivatives on Measures of Financial Performance Currently, the Company does not seek cash flow hedge accounting treatment for its currency- or coal-related derivative financial instruments and thus changes in fair value are reflected in current earnings. The tables below show the amounts of pre-tax gains and losses related to the Company’s derivatives. Three Months Ended March 31, 2019 Total (loss) gain recognized in income (Loss) gain realized in income on derivatives Unrealized (loss) gain recognized in income on derivatives Financial Instrument (Dollars in millions) Foreign currency option contracts $ (1.1 ) $ (1.3 ) $ 0.2 Coal contracts related to forecasted sales 50.7 10.9 39.8 Coal trading contracts (1.1 ) (4.8 ) 3.7 Total $ 48.5 $ 4.8 $ 43.7 Three Months Ended March 31, 2018 Total (loss) gain recognized in income (Loss) gain realized in income on derivatives Unrealized (loss) gain recognized in income on derivatives Financial Instrument (Dollars in millions) Foreign currency option contracts $ (4.2 ) $ (2.4 ) $ (1.8 ) Coal contracts related to forecasted sales 59.8 21.2 38.6 Coal trading contracts (1.0 ) (2.8 ) 1.8 Total $ 54.6 $ 16.0 $ 38.6 During the three months ended March 31, 2019 and 2018 , gains and losses on foreign currency option contracts were included in “Operating costs and expenses,” and gains and losses on coal contracts related to forecasted sales and those related to coal trading contracts were included in “Revenues” in the accompanying unaudited condensed consolidated statements of operations. The Company classifies the cash effects of its derivatives within the “Cash Flows From Operating Activities” section of the unaudited condensed consolidated statements of cash flows. Fair Value Measurements The Company uses a three-level fair value hierarchy that categorizes assets and liabilities measured at fair value based on the observability of the inputs utilized in the valuation. These levels include: Level 1 - inputs are quoted prices in active markets for the identical assets or liabilities; Level 2 - inputs are other than quoted prices included in Level 1 that are directly or indirectly observable through market-corroborated inputs; and Level 3 - inputs are unobservable, or observable but cannot be market-corroborated, requiring the Company to make assumptions about pricing by market participants. The following tables set forth the hierarchy of the Company’s net financial asset positions for which fair value is measured on a recurring basis: March 31, 2019 Level 1 Level 2 Level 3 Total (Dollars in millions) Foreign currency option contracts $ — $ 1.3 $ — $ 1.3 Coal contracts related to forecasted sales — 18.8 — 18.8 Coal trading contracts — (14.7 ) — (14.7 ) Equity securities — — 10.0 10.0 Total net financial assets $ — $ 5.4 $ 10.0 $ 15.4 December 31, 2018 Level 1 Level 2 Level 3 Total (Dollars in millions) Foreign currency option contracts $ — $ 1.2 $ — $ 1.2 Coal contracts related to forecasted sales — (21.2 ) — (21.2 ) Coal trading contracts — 21.8 — 21.8 Equity securities — — 10.0 10.0 Total net financial assets $ — $ 1.8 $ 10.0 $ 11.8 For Level 1 and 2 financial assets and liabilities, the Company utilizes both direct and indirect observable price quotes, including interest rate yield curves, exchange indices, broker/dealer quotes, published indices, issuer spreads, benchmark securities and other market quotes. In the case of certain debt securities, fair value is provided by a third-party pricing service. Below is a summary of the Company’s valuation techniques for Level 1 and 2 financial assets and liabilities: • Foreign currency option contracts: valued utilizing inputs obtained in quoted public markets (Level 2) except when credit and non-performance risk is considered to be a significant input, then the Company classifies such contracts as Level 3. • Coal contracts related to forecasted sales and coal trading contracts: generally valued based on unadjusted quoted prices in active markets (Level 1) or a valuation that is corroborated by the use of market-based pricing (Level 2) except when credit and non-performance risk is considered to be a significant input (greater than 10% of fair value), then the Company classifies as Level 3. • Investments in equity securities are based on observed prices in an inactive market (Level 3). Other Financial Instruments . The following methods and assumptions were used by the Company in estimating fair values for other financial instruments as of March 31, 2019 and December 31, 2018 : • Cash and cash equivalents, restricted cash, accounts receivable, including those within the Company’s accounts receivable securitization program, notes receivable and accounts payable have carrying values which approximate fair value due to the short maturity or the liquid nature of these instruments. • Long-term debt fair value estimates are based on observed prices for securities with an active trading market when available (Level 2), and otherwise on estimated borrowing rates to discount the cash flows to their present value (Level 3). The carrying amount and estimated fair values of the Company’s current and long-term debt as of March 31, 2019 and December 31, 2018 are summarized as follows: March 31, 2019 December 31, 2018 Carrying Estimated Carrying Estimated (Dollars in millions) Current and Long-term debt $ 1,361.7 $ 1,406.6 $ 1,367.0 $ 1,366.2 The Company’s risk management function, which is independent of the Company’s coal trading function, is responsible for valuation policies and procedures, with oversight from executive management. Generally, the Company’s Level 3 instruments or contracts are valued using bid/ask price quotations and other market assessments obtained from multiple, independent third-party brokers or other transactional data incorporated into internally-generated discounted cash flow models. Decreases in the number of third-party brokers or market liquidity could erode the quality of market information and therefore the valuation of the Company’s market positions. The Company’s valuation techniques include basis adjustments to the foregoing price inputs for quality, such as sulfur and ash content, location differentials, expressed as port and freight costs, and credit risk. The Company’s risk management function independently validates the Company’s valuation inputs, including unobservable inputs, with third-party information and settlement prices from other sources where available. A daily process is performed to analyze market price changes and changes to the portfolio. Further periodic validation occurs at the time contracts are settled with the counterparty. These valuation techniques have been consistently applied in all periods presented, and the Company believes it has obtained the most accurate information available for the types of derivative contracts held. Significant increases or decreases in the inputs in isolation could result in a significantly higher or lower fair value measurement. The unobservable inputs do not have a direct interrelationship; therefore, a change in one unobservable input would not necessarily correspond with a change in another unobservable input. The Company had no transfers between Levels 1, 2 and 3 during the three months ended March 31, 2019 and 2018. The Company’s policy is to value all transfers between levels using the beginning of period valuation. Credit and Nonperformance Risk. The fair value of the Company’s coal derivative assets and liabilities reflects adjustments for credit risk. The Company’s exposure is substantially with electric utilities, energy marketers, steel producers and nonfinancial trading houses. The Company’s policy is to independently evaluate each customer’s creditworthiness prior to entering into transactions and to regularly monitor the credit extended. If the Company engages in a transaction with a counterparty that does not meet its credit standards, the Company seeks to protect its position by requiring the counterparty to provide an appropriate credit enhancement. Also, when appropriate (as determined by its credit management function), the Company has taken steps to reduce its exposure to customers or counterparties whose credit has deteriorated and who may pose a higher risk of failure to perform under their contractual obligations. These steps include obtaining letters of credit or cash collateral (margin), requiring prepayments for shipments or the creation of customer trust accounts held for the Company’s benefit to serve as collateral in the event of a failure to pay or perform. To reduce its credit exposure related to trading and brokerage activities, the Company seeks to enter into netting agreements with counterparties that permit the Company to offset asset and liability positions with such counterparties and, to the extent required, the Company will post or receive margin amounts associated with exchange-cleared and certain OTC positions. The Company also continually monitors counterparty and contract non-performance risk, if present, on a case-by-case basis. As of March 31, 2019 , 43% of the Company’s credit exposure related to coal trading activities was with investment grade counterparties and 57% was with counterparties that are not rated. Performance Assurances and Collateral The Company is required to post variation margin on positions that are in a net liability position and is entitled to receive and hold variation margin on positions that are in a net asset position with an exchange and certain of its OTC derivative contract counterparties. As of March 31, 2019 , the Company was in receipt of $18.2 million in variation margin, while it had posted $21.8 million of net variation margin at December 31, 2018 . In addition to the requirements surrounding variation margin, the Company is required by the exchanges upon which it transacts to post certain additional collateral, known as initial margin, which represents an estimate of potential future adverse price movements across the Company’s portfolio under normal market conditions. The Company posted initial margin of $15.5 million and $16.7 million as of March 31, 2019 and December 31, 2018 , respectively, which is reflected in “Other current assets” in the condensed consolidated balance sheets. As of March 31, 2019 , the Company had posted $6.0 million in excess of initial margin requirements, while as of December 31, 2018 , the Company was in receipt of $2.2 million . Certain of the Company’s derivative trading instruments require the parties to provide additional performance assurances whenever a material adverse event jeopardizes one party’s ability to perform under the instrument. If the Company was to sustain a material adverse event (using commercially reasonable standards), its counterparties could request collateralization on derivative trading instruments in net liability positions which, based on an aggregate fair value at March 31, 2019 and December 31, 2018 , would have amounted to collateral postings to counterparties of approximately $0.1 million and $1.3 million , respectively. As of March 31, 2019 and December 31, 2018 , the Company was not required to post collateral to counterparties for such positions.

Intangible Contract Assets and

Intangible Contract Assets and Liabilities	3 Months Ended
	Mar. 31, 2019
Revenue Recognition [Abstract]
Intangible Contract Assets and Liabilities	Intangible Contract Assets and Liabilities As described in Note 2. “Emergence from the Chapter 11 Cases and Fresh Start Reporting” in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 and Note 3. “Acquisition of Shoal Creek Mine,” the Company has recorded intangible assets and liabilities to reflect the fair value of certain U.S. coal supply agreements as a result of differences between contract terms and estimated market terms for the same coal products, and also recorded intangible liabilities related to unutilized capacity under its port and rail take-or-pay contracts. The balances, net of accumulated amortization, and respective balance sheet classifications at March 31, 2019 and December 31, 2018 , are set forth in the following tables: March 31, 2019 (Dollars in millions) Assets Liabilities Net Total Coal supply agreements $ 60.5 $ (27.3 ) $ 33.2 Take-or-pay contracts — (51.8 ) (51.8 ) Total $ 60.5 $ (79.1 ) $ (18.6 ) Balance sheet classification: Investments and other assets $ 60.5 $ — $ 60.5 Accounts payable and accrued expenses — (14.0 ) (14.0 ) Other noncurrent liabilities — (65.1 ) (65.1 ) Total $ 60.5 $ (79.1 ) $ (18.6 ) December 31, 2018 (Dollars in millions) Assets Liabilities Net Total Coal supply agreements $ 70.9 $ (32.9 ) $ 38.0 Take-or-pay contracts — (57.1 ) (57.1 ) Total $ 70.9 $ (90.0 ) $ (19.1 ) Balance sheet classification: Investments and other assets $ 70.9 $ — $ 70.9 Accounts payable and accrued expenses — (20.3 ) (20.3 ) Other noncurrent liabilities — (69.7 ) (69.7 ) Total $ 70.9 $ (90.0 ) $ (19.1 ) Amortization of the intangible assets and liabilities related to coal supply agreements occurs ratably based upon coal volumes shipped per contract and is recorded as a component of “Depreciation, depletion and amortization” in the accompanying unaudited condensed consolidated statements of operations. Such amortization amounted to $4.8 million and $29.3 million during the three months ended March 31, 2019 and 2018, respectively. The Company anticipates net amortization of sales contracts, based upon expected shipments, to be an expense of approximately $22 million during the remaining nine months of 2019, and for the years 2020 through 2023 , expense of approximately $8 million , $3 million , $1 million and $1 million , respectively. Future unutilized capacity and the amortization periods related to the take-or-pay contract intangible liabilities are based upon estimates of forecasted usage. Such amortization, which is classified as a reduction to “Operating costs and expenses” in the accompanying unaudited condensed consolidated statements of operations, amounted to $5.6 million and $8.3 million during the three months ended March 31, 2019 and 2018, respectively. The Company anticipates net amortization of take-or-pay contract intangible liabilities to be approximately $11 million during the remaining nine months of 2019, and for the years 2020 through 2023 , approximately $9 million , $4 million , $3 million and $3 million , respectively, and $22 million thereafter.

Property, Plant, Equipment and

Property, Plant, Equipment and Mine Development	3 Months Ended
	Mar. 31, 2019
Property, Plant and Equipment [Abstract]
Property, Plant, Equipment and Mine Development	Property, Plant, Equipment and Mine Development The composition of property, plant, equipment and mine development, net, as of March 31, 2019 and December 31, 2018 is set forth in the table below: March 31, 2019 December 31, 2018 (Dollars in millions) Land and coal interests $ 4,149.8 $ 4,148.8 Buildings and improvements 558.3 559.3 Machinery and equipment 1,474.0 1,456.3 Less: Accumulated depreciation, depletion and amortization (1,112.6 ) (957.4 ) Property, plant, equipment and mine development, net $ 5,069.5 $ 5,207.0

Leases

Leases	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Leases of Lessee Disclosure [Text Block]	Leases The Company has operating and finance leases for mining and non-mining equipment, office space, and certain other facilities under various non-cancellable agreements. Historically, the majority of the Company’s leases have been accounted for as operating leases. The Company determines if an arrangement is a lease at inception. ROU assets represent the Company's right to use an underlying asset for the lease term and lease liabilities represent its obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. For the purpose of calculating such present values, lease payments include components that vary based upon an index or rate, using the prevailing index or rate at the commencement date, and exclude components that vary based upon other factors. As most of its leases do not provide an implicit rate, the Company uses its incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. The Company's leases may include options to extend or terminate the lease, and such options are reflected in the term when their exercise is reasonably certain. Lease expense is recognized on a straight-line basis over the lease term. For certain equipment leases, the Company applies a portfolio approach to effectively account for the operating lease ROU assets and liabilities. The Company and certain of its subsidiaries have guaranteed other subsidiaries’ performance under various lease obligations. Certain lease agreements are subject to the restrictive covenants of the Company’s credit facilities and include cross-acceleration provisions, under which the lessor could require remedies including, but not limited to, immediate recovery of the present value of any remaining lease payments. The Company typically agrees to indemnify lessors for the value of the property or equipment leased, should the property be damaged or lost during the course of the Company’s operations. The Company expects that losses with respect to leased property, if any, may be covered by insurance (subject to deductibles). Aside from indemnification of the lessor for the value of the property leased, the Company’s maximum potential obligations under its leases are equal to the respective future minimum lease payments, and the Company assumes that no amounts could be recovered from third parties. In this regard, the Company has recorded provisions amounting to $50.7 million related to the loss of leased equipment at its North Goonyella Mine as described in Note 16. “Other Events.” One of the Company’s operating lease agreements for underground mining equipment in Australia entered into in 2013 requires contingent rent to be paid only if and when certain coal is mined at a specified margin as defined in the agreements. There was no contingent expense related to that arrangement for the periods listed below. The components of lease expense during the three months ended March 31, 2019 were as follows: Three Months Ended March 31, 2019 (Dollars in millions) Operating lease cost: Operating lease cost $ 15.5 Short-term lease cost 8.3 Variable lease cost 6.0 Sublease income (1.4 ) Total operating lease cost $ 28.4 Finance lease cost: Amortization of right-of-use assets $ 4.1 Interest on lease liabilities 0.5 Total finance lease cost $ 4.6 Rental expense under operating leases, including expense related to short-term operating leases, was $44.7 million during the three months ended March 31, 2018. Supplemental balance sheet information related to leases at March 31, 2019 was as follows: March 31, 2019 (Dollars in millions) Operating leases: Operating lease right-of-use assets $ 97.0 Accounts payable and accrued expenses $ 30.7 Operating lease liabilities, less current portion 58.2 Total operating lease liabilities $ 88.9 Finance leases: Property, plant, equipment and mine development $ 97.8 Accumulated depreciation (33.4 ) Property, plant, equipment and mine development, net $ 64.4 Current portion of long-term debt $ 30.8 Long-term debt, less current portion 1.9 Total finance lease liabilities $ 32.7 Weighted average remaining lease term Operating leases 4.2 years Finance leases 5.4 years Weighted average discount rate Operating leases 7.4 % Finance leases 7.6 % Supplemental cash flow information related to leases during the three months ended March 31, 2019 was as follows: Three Months Ended March 31, 2019 (Dollars in millions) Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows for operating leases $ 24.1 Operating cash flows for finance leases 0.7 Financing cash flows for finance leases 7.3 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 0.5 Finance leases — The Company's leases have remaining lease terms of 1 year to 23 years , some of which include options to extend the terms deemed reasonably certain of exercise. Maturities of lease liabilities were as follows: Period Ending December 31, Operating Leases Finance Leases (Dollars in millions) 2019 $ 27.0 $ 28.7 2020 28.0 8.1 2021 16.5 0.5 2022 11.9 0.5 2023 12.2 0.5 2024 and thereafter 12.1 8.7 Total lease payments 107.7 47.0 Less imputed interest (18.8 ) (14.3 ) Total lease liabilities $ 88.9 $ 32.7

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company’s income tax provision of $18.8 million and $10.1 million for the three months ended March 31, 2019 and 2018, respectively, included a tax benefit of less than $0.1 million and a tax provision of $0.5 million , respectively, related to the remeasurement of foreign income tax accounts. The Company’s effective tax rate before remeasurement for the three months ended March 31, 2019 is based on the Company’s estimated full year effective tax rate, comprised of expected statutory tax provision, offset by foreign rate differential and changes in valuation allowances.

Long-term Debt

Long-term Debt	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
Long-term Debt	Long-term Debt The Company’s total indebtedness as of March 31, 2019 and December 31, 2018 consisted of the following: March 31, 2019 December 31, 2018 (Dollars in millions) 6.000% Senior Secured Notes due March 2022 $ 500.0 $ 500.0 6.375% Senior Secured Notes due March 2025 500.0 500.0 Senior Secured Term Loan due 2025, net of original issue discount 395.0 395.9 Finance lease and other obligations 32.7 40.0 Less: Debt issuance costs (66.0 ) (68.9 ) 1,361.7 1,367.0 Less: Current portion of long-term debt 34.8 36.5 Long-term debt $ 1,326.9 $ 1,330.5 6.000% and 6.375% Senior Secured Notes On February 15, 2017, one of PEC’s subsidiaries entered into an indenture (the Indenture) with Wilmington Trust, National Association, as trustee, relating to the issuance by PEC’s subsidiary of $500.0 million aggregate principal amount of 6.000% senior secured notes due 2022 (the 2022 Notes) and $500.0 million aggregate principal amount of 6.375% senior secured notes due 2025 (the 2025 Notes and, together with the 2022 Notes, the Senior Notes). The Senior Notes were sold on February 15, 2017 in a private transaction exempt from the registration requirements of the Securities Act of 1933. The Senior Notes were issued at par value. The Company paid aggregate debt issuance costs of $49.5 million related to the offering, which are being amortized over the respective terms of the Senior Notes. Interest payments on the Senior Notes are scheduled to occur each year on March 31st and September 30th until maturity. During the three months ended March 31, 2019 and 2018, the Company recorded interest expense of $18.0 million and $17.5 million , respectively, related to the Senior Notes. The Company may redeem the 2022 Notes, in whole or in part, beginning in 2019 at 103.0% of par, in 2020 at 101.5% of par, and in 2021 and thereafter at par. The 2025 Notes may be redeemed, in whole or in part, beginning in 2020 at 104.8% of par, in 2021 at 103.2% of par, in 2022 at 101.6% of par, and in 2023 and thereafter at par. In addition, prior to the first date on which the Senior Notes are redeemable at the redemption prices noted above, the Company may also redeem some or all of the Senior Notes at a calculated make-whole premium, plus accrued and unpaid interest. On August 9, 2018, the Company executed an amendment to the Indenture following the solicitation of consents from the requisite majorities of holders of each series of Senior Notes. The amendment permits a category of restricted payments at any time not to exceed the sum of $650.0 million , plus an additional $150.0 million per calendar year, commencing with calendar year 2019, with unused amounts in any calendar year carrying forward to and available for restricted payments in any subsequent calendar year. The Company paid consenting Senior Note holders $10.00 in cash per $1,000 principal amount of 2022 Notes and $30.00 in cash per $1,000 principal amount of 2025 Notes, which amounted to $19.8 million in aggregate consent payments. Such consent payments were capitalized as additional debt issuance costs to be amortized over the respective terms of the Senior Notes. The Company also expensed $1.5 million of other payments associated with the amendment to “Interest expense” in the accompanying unaudited condensed consolidated statements of operations during 2018. The Indenture contains customary conditions of default and imposes certain restrictions on the Company’s activities, including its ability to incur liens, incur debt, make investments, engage in fundamental changes such as mergers and dissolutions, dispose of assets, enter into transactions with affiliates and make certain restricted payments, such as cash dividends and share repurchases. The Senior Notes rank senior in right of payment to any subordinated indebtedness and equally in right of payment with any senior indebtedness to the extent of the collateral securing that indebtedness. The Senior Notes are jointly and severally and fully and unconditionally guaranteed on a senior secured basis by substantially all of the Company’s material domestic subsidiaries and secured by first priority liens over (1) substantially all of the assets of the Company and the guarantors, except for certain excluded assets, (2) 100% of the capital stock of each domestic restricted subsidiary of the Company, (3) 100% of the non-voting capital stock of each first tier foreign subsidiary of the Company or a foreign subsidiary holding company and no more than 65% of the voting capital stock of each first tier foreign subsidiary of the Company or a foreign subsidiary holding company, (4) a legal charge of 65% of the voting capital stock and 100% of the non-voting capital stock of Peabody Investments (Gibraltar) Limited and (5) all intercompany debt owed to the Company or any guarantor, in each case, subject to certain exceptions. The obligations under the Senior Notes are secured on a pari passu basis by the same collateral securing the Credit Agreement (as defined below), subject to certain exceptions. Credit Agreement The Company entered into a credit agreement, dated as of April 3, 2017, among the Company, as borrower, Goldman Sachs Bank USA, as administrative agent, and other lenders party thereto (the Credit Agreement). The Credit Agreement originally provided for a $950.0 million senior secured term loan (the Senior Secured Term Loan), which was to mature in 2022 prior to the amendments described below. Following the voluntary prepayments and amendments described below, the Credit Agreement provided for a $400.0 million first lien senior secured term loan, which bore interest at LIBOR plus 2.75% per annum as of March 31, 2019 . During the three months ended March 31, 2019 and 2018, the Company recorded interest expense of $5.7 million and $6.6 million , respectively, related to the Senior Secured Term Loan. Proceeds from the Senior Secured Term Loan were received net of an original issue discount and deferred financing costs of $37.3 million that are being amortized over its term. The loan principal is payable in quarterly installments plus accrued interest through December 2024 with the remaining balance due in March 2025. The loan principal was voluntarily prepayable at 101% of the principal amount repaid if voluntarily prepaid prior to October 2018 (subject to certain exceptions, including prepayments made with internally generated cash) and is voluntarily prepayable at any time thereafter without premium or penalty. The Senior Secured Term Loan may require mandatory principal prepayments of up to 75% of Excess Cash Flow (as defined in the Credit Agreement) for any fiscal year if the Company’s Total Leverage Ratio (as defined in the Credit Agreement and calculated at December 31, net of any unrestricted cash) is greater than 2.00 :1.00. The mandatory principal prepayment requirement changes to (i) 50% of Excess Cash Flow if the Company’s Total Leverage Ratio is less than or equal to 2.00 :1.00 and greater than 1.50 :1.00, (ii) 25% of Excess Cash Flow if the Company’s Total Leverage Ratio is less than or equal to 1.50 :1.00 and greater than 1.00 :1.00, or (iii) zero if the Company’s Total Leverage Ratio is less than or equal to 1.00 :1.00. If required, mandatory prepayments resulting from Excess Cash Flows are payable within 100 days after the end of each fiscal year. The calculation of mandatory prepayments would be reduced commensurately by the amount of previous voluntary prepayments. In certain circumstances, the Senior Secured Term Loan requires that Excess Proceeds (as defined in the Credit Agreement) of $10.0 million or greater received from sales of Company assets be applied against the loan principal, unless such proceeds are reinvested within one year. The Senior Secured Term Loan also requires that any net insurance proceeds be applied against the loan principal, unless such proceeds are reinvested within one year. The Credit Agreement contains customary conditions of default and imposes certain restrictions on the Company’s activities, including its ability to incur liens, incur debt, make investments, engage in fundamental changes such as mergers and dissolutions, dispose of assets, enter into transactions with affiliates, and make certain restricted payments, such as cash dividends and share repurchases. Obligations under the Credit Agreement are secured on a pari passu basis by the same collateral securing the Senior Notes. Since entering into the Credit Agreement, the Company has repaid $554.0 million of the original $950.0 million loan principal amount on the Senior Secured Term Loan in various installments, including $546.0 million which was voluntarily prepaid. In September 2017, the Company entered into an amendment to the Credit Agreement which permitted the Company to add an incremental revolving credit facility in addition to the Company’s ability to add one or more incremental term loan facilities under the Credit Agreement. The incremental revolving credit facility and/or incremental term loan facilities can be in an aggregate principal amount of up to $350.0 million plus additional amounts so long as the Company is below Total Leverage Ratio requirements as set forth in the Credit Agreement. The amendment also made available an additional restricted payment basket that permits additional repurchases, dividends or other distributions with respect to the Company’s common and preferred stock in an aggregate amount up to $450.0 million so long as the Company’s Fixed Charge Coverage Ratio (as defined in the Credit Agreement) would not exceed 2.00 :1.00 on a pro forma basis. During the fourth quarter of 2017, the Company entered into the incremental revolving credit facility (the Revolver) for an aggregate commitment of $350.0 million for general corporate purposes. The Company paid aggregate debt issuance costs of $4.7 million . The Revolver matures in November 2020 and permits loans which bear interest at LIBOR plus 3.25% . The Revolver is subject to a 2.00 :1.00 Total Leverage Ratio requirement (as defined in the Credit Agreement), modified to limit unrestricted cash netting to $800.0 million . Capacity under the Revolver may also be utilized for letters of credit which incur combined fees of 3.375% per annum. Unused capacity under the Revolver bears a commitment fee of 0.5% per annum. As of March 31, 2019 , the Revolver had only been utilized for letters of credit amounting to $106.5 million . Such letters of credit were primarily in support of the Company’s reclamation obligations, as further described in Note 18. “Financial Instruments and Other Guarantees.” During the three months ended March 31, 2019 and 2018, the Company recorded interest expense and fees of $1.6 million and $1.8 million , respectively, related to the Revolver. In April 2018, the Company entered into another amendment to the Credit Agreement which lowered the interest rate on the Senior Secured Term Loan to its current level of LIBOR plus 2.75% and eliminated an existing 1.0% LIBOR floor. The amendment also extended the maturity of the Senior Secured Term Loan by three years to 2025 and eliminated previous capital expenditure restriction covenants on both the Senior Secured Term Loan and the Revolver. In connection with this amendment, the Company voluntarily repaid $46.0 million of principal on the Senior Secured Term Loan. Restricted Payments Under the Senior Notes and Credit Agreement In addition to the $450.0 million restricted payment basket provided for under the September 2017 amendment, the Credit Agreement provides a builder basket for additional restricted payments subject to a maximum Total Leverage Ratio of 2.00 :1.00 (as defined in the Credit Agreement). In addition to the $650.0 million restricted payment basket, plus an additional $150.0 million per calendar year, provided under the August 2018 amendment, the Indenture provides a builder basket for restricted payments that is calculated based upon the Company’s Consolidated Net Income, and is subject to a Fixed Charge Coverage Ratio of at least 2.25 :1.00 (as defined in the Indenture). Further, under both the Indenture and Credit Agreement, additional restricted payments are permitted through a $50.0 million general basket and an annual aggregate $25.0 million basket which allows dividends and common stock repurchases. The payment of dividends and purchases of common stock under this annual aggregate $25.0 million basket are permitted so long as the Company’s Total Leverage Ratio would not exceed 1.25 :1.00 on a pro forma basis (as defined in the Credit Agreement and Indenture). Copies of the Indenture documents are incorporated as Exhibits 4.2 and 4.3 to the Current Report on Form 8-K filed by the Company with the Securities and Exchange Commission (SEC) on April 3, 2017. A copy of the Credit Agreement is included as Exhibit 10.3 to the Current Report on Form 8-K filed by the Company with the SEC on April 3, 2017, and copies of the subsequent amendments referenced above are included as Exhibits 10.1 to the Current Reports on Form 8-K filed by the Company with the SEC on September 18, 2017, November 20, 2017, December 19, 2017 and April 11, 2018, and as Exhibit 10.1 to the Quarterly Report on Form 10-Q filed by the Company with the SEC on November 1, 2018. Finance Lease Obligations Refer to Note 11. “Leases” for additional information associated with the Company’s finance leases, which pertain to the financing of mining equipment used in operations.

Pension and Postretirement Bene

Pension and Postretirement Benefit Costs	3 Months Ended
	Mar. 31, 2019
Retirement Benefits [Abstract]
Pension and Postretirement Benefit Costs	Pension and Postretirement Benefit Costs The components of net periodic pension and postretirement benefit costs, excluding the service cost for benefits earned, are included in “Net periodic benefit costs, excluding service cost” in the unaudited condensed consolidated statements of operations. Net periodic pension cost (benefit) included the following components: Three Months Ended March 31, 2019 2018 (Dollars in millions) Service cost for benefits earned $ 0.5 $ 0.6 Interest cost on projected benefit obligation 8.3 7.8 Expected return on plan assets (7.8 ) (10.7 ) Net periodic pension cost (benefit) $ 1.0 $ (2.3 ) Annual contributions to the qualified plans are made in accordance with minimum funding standards and the Company’s agreement with the Pension Benefit Guaranty Corporation. Funding decisions also consider certain funded status thresholds defined by the Pension Protection Act of 2006 (generally 80% ). As of March 31, 2019 , the Company’s qualified plans were expected to be at or above the Pension Protection Act thresholds. Minimum funding standards are legislated by ERISA and are modified by pension funding stabilization provisions included in the Moving Ahead for Progress in the 21st Century Act of 2012, the Highway and Transportation Funding Act of 2014 and the Bipartisan Budget Act of 2015. The Company is not required to make any contributions to its qualified pension plans based on minimum funding requirements; however, the Company expects to make discretionary contributions to its qualified pension plans in 2019. Net periodic postretirement benefit cost included the following components: Three Months Ended March 31, 2019 2018 (Dollars in millions) Service cost for benefits earned $ 1.2 $ 2.0 Interest cost on accumulated postretirement benefit obligation 6.3 7.1 Expected return on plan assets (0.1 ) — Amortization of prior service credit (2.2 ) — Net periodic postretirement benefit cost $ 5.2 $ 9.1 In October 2018, the Company amended its postretirement health care benefit plan which reduced the Company’s accumulated postretirement benefit obligation, as further described in Note 17. “Postretirement Health Care and Life Insurance Benefits” in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018. The reduction in liability has been recorded with an offsetting balance in accumulated other comprehensive income, net of a deferred tax provision, and is being amortized to earnings over an average remaining service period to full eligibility for participating employees. In 2018, the Company established a Voluntary Employees Beneficiary Association (VEBA) trust to pre-fund a portion of benefits for non-represented retirees. The Company expects to make discretionary contributions to the VEBA in 2019.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	3 Months Ended
	Mar. 31, 2019
Equity [Abstract]
Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income The following table sets forth the after-tax components of accumulated other comprehensive income and changes thereto recorded during the three months ended March 31, 2019 : Foreign Currency Translation Adjustment Prior Service Credit (Cost) Associated with Postretirement Plans Total Accumulated Other Comprehensive Income (Dollars in millions) December 31, 2018 $ (4.5 ) $ 44.6 $ 40.1 Reclassification from other comprehensive income to earnings — (2.2 ) (2.2 ) Current period change 0.1 — 0.1 March 31, 2019 $ (4.4 ) $ 42.4 $ 38.0 Postretirement health care and life insurance benefits reclassified out of “Accumulated other comprehensive income” into earnings of $2.2 million is presented as “Net periodic benefit costs, excluding service costs” in the unaudited condensed consolidated statements of operations.

Other Events

Other Events	3 Months Ended
	Mar. 31, 2019
Other Events [Abstract]
Other Events	Other Events North Goonyella The Company’s North Goonyella Mine in Queensland, Australia experienced a fire in a portion of the mine during September 2018. Mining operations have been suspended since September 2018. No mine personnel were physically harmed by the September 2018 events. On November 13, 2018, the Queensland Mine Inspectorate (QMI) initiated an investigation into the events that occurred at the mine to determine the cause of the event, assess the response to it and make recommendations to reduce the possibility of future incidents and improve response. The Company is currently complying with administrative requests from the QMI following a thorough review. During the first quarter of 2019, the Company completed segmenting of the mine into multiple zones to facilitate a phased re-ventilation and re-entry of the mine. In addition, all physical activities in advance of re-ventilating the first segment of the mine were completed. During the year ended December 31, 2018, the Company recorded $58.0 million in containment and idling costs related to the events at North Goonyella and a provision of $66.4 million for expected equipment losses. During the three months ended March 31, 2019, the Company recorded an additional $36.9 million in containment and idling costs, and an additional provision of $24.7 million related to equipment losses as more information became available. The combined provision includes $50.7 million for the estimated cost to replace leased equipment, $23.2 million related to the cost of Company-owned equipment and $17.2 million of other charges, which represents the best estimate of potential loss based on the assessments made to date. In the event that no future mining occurs at the North Goonyella Mine, the Company may record additional charges for the remaining carrying value of the North Goonyella Mine and additional leased equipment of approximately $275 million and $10 million , respectively. Incremental exposures above the aforementioned include take-or-pay obligations and other costs associated with idling or closing the mine. In March 2019, the Company entered into an insurance claim settlement agreement with its insurers and various re-insurers under a combined property damage and business interruption policy and recorded a $125 million insurance recovery, the maximum amount available under the policy above a $50 million deductible. The Company collected $8.1 million of the recovery during March 2019 and the remainder subsequent to March 31, 2019. On April 30, 2019, Peabody (Bowen) Pty Ltd entered into an option exercise and release agreement with Yancoal Technology Development Pty Ltd pursuant to which Peabody (Bowen) Pty Ltd exercised an option to acquire from Yancoal Technology Development Pty Ltd the longwall mining equipment used under license at the North Goonyella Mine for $54.2 million , which was consistent with the Company’s provision for equipment losses for the related impaired assets at March 31, 2019. Divestitures In June 2018, Peabody entered into an agreement to sell approximately 23 million tonnes of metallurgical coal resources adjacent to its Millennium Mine to Stanmore Coal Limited (Stanmore) for approximately $22 million . The sale was completed in July 2018. During the three months ended March 31, 2019 , Stanmore paid Peabody approximately $7 million , which brought the remaining receivable balance to approximately $7 million as of March 31, 2019. The remaining receivable balance, which will be paid over the subsequent four months, is included in “Accounts receivable, net” in the accompanying condensed consolidated balance sheet. On February 6, 2018, the Company sold its 50% interest in the Red Mountain Joint Venture (RMJV) with BHP Billiton Mitsui Coal Pty Ltd (BMC) for $20.0 million and recorded a gain of $7.1 million , which is included within “ Net gain on disposals ” in the accompanying unaudited condensed consolidated statements of operations for the three months ended March 31, 2018 . RMJV operated the coal handling and preparation plant utilized by the Company’s Millennium Mine. BMC assumed the reclamation obligations and other commitments associated with the assets of RMJV. The Millennium Mine will have continued usage of the coal handling and preparation plant and the associated rail loading facility until the end of 2019 via a coal washing take-or-pay agreement with BMC. In January 2018, Peabody entered into an agreement to sell its share in certain surplus land assets in Queensland’s Bowen Basin to Pembroke Resources South Pty Ltd for approximately $37 million Australian dollars, net of transaction costs. The necessary approval of the Australian Foreign Investment Review Board to complete the transaction was received on March 29, 2018, satisfying all the conditions precedent to the sale, and the Company recorded a gain of $20.6 million , which is included within “ Net gain on disposals ” in the accompanying unaudited condensed consolidated statements of operations for the three months ended March 31, 2018 . Joint Venture In 2014, the Company agreed to establish an unincorporated joint venture project with Glencore plc (Glencore), in which the Company holds a 50% interest, to combine the existing operations of the Company’s Wambo Open-Cut Mine in Australia with the adjacent coal reserves of Glencore’s United Mine. The Company expects the project to result in several operational synergies, including improved mining productivity, lower per-unit operating costs and an extended mine life. The joint venture is expected to be formed during 2019, subject to substantive contingencies for the requisite regulatory and permitting approvals. At such time as control over the existing operations is exchanged, the Company will account for its interest in the combined operations at fair value.

Earnings per Share (EPS)

Earnings per Share (EPS)	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Earnings per Share (EPS)	Earnings per Share (EPS) Basic EPS is computed based on the weighted average number of shares of common stock outstanding during the period. Diluted EPS is computed based on the weighted average number of shares of common stock plus the effect of dilutive potential common shares outstanding. As such, the Company includes the share-based compensation awards in its potentially dilutive securities. Dilutive securities are not included in the computation of loss per share when a company reports a net loss from continuing operations as the impact would be anti-dilutive. During the periods which included the Company’s convertible preferred stock, basic and diluted EPS were computed using the two-class method, which is an earnings allocation that determines EPS for each class of common stock and participating securities according to dividends declared and participation rights in undistributed earnings. The Company’s convertible preferred stock was considered a participating security because holders were entitled to receive dividends on an if-converted basis. Diluted EPS assumes that participating securities are not executed or converted. For all but the performance units, the potentially dilutive impact of the Company’s share-based compensation awards is determined using the treasury stock method. Under the treasury stock method, awards are treated as if they had been exercised with any proceeds used to repurchase common stock at the average market price during the period. Any incremental difference between the assumed number of shares issued and purchased is included in the diluted share computation. For the performance units, their contingent features result in an assessment for any potentially dilutive common stock by using the end of the reporting period as if it were the end of the contingency period for all units granted. The computation of diluted EPS excluded aggregate share-based compensation awards of approximately 0.3 million and less than 0.1 million for the three months ended March 31, 2019 and 2018 , respectively, because to do so would have been anti-dilutive for those periods. Because the potential dilutive impact of such share-based compensation awards is calculated under the treasury stock method, anti-dilution generally occurs when the exercise prices or unrecognized compensation cost per share of such awards are higher than the Company’s average stock price during the applicable period. The following illustrates the earnings allocation method utilized in the calculation of basic and diluted EPS. Three Months Ended March 31, 2019 2018 (In millions, except per share data) EPS numerator: Income from continuing operations, net of income taxes $ 133.3 $ 208.3 Less: Series A Convertible Preferred Stock dividends — 102.5 Less: Net income (loss) attributable to noncontrolling in terests 5.7 (2.1 ) Income from continuing operations attributable to common stockholders, before allocation of earnings to participating securities 127.6 107.9 Less: Earnings allocated to participating securities — 6.0 Income from continuing operations attributable to common stockholders, after allocation of earnings to participating securities (1) 127.6 101.9 Loss from discontinued operations, net of income taxes (3.4 ) (1.3 ) Less: Loss from discontinued operations allocated to participating securities — (0.1 ) Loss from discontinued operations attributable to common stockholders, after allocation of earnings to participating securities (3.4 ) (1.2 ) Net income attributable to common stockholders, after allocation of earnings to participating securities (1) $ 124.2 $ 100.7 EPS denominator: Weighted average shares outstanding — basic 108.5 120.9 Impact of dilutive securities 2.0 2.3 Weighted average shares outstanding — diluted (2) 110.5 123.2 Basic EPS attributable to common stockholders: Income from continuing operations $ 1.18 $ 0.84 Loss from discontinued operations (0.04 ) (0.01 ) Net income attributable to common stockholders $ 1.14 $ 0.83 Diluted EPS attributable to common stockholders: Income from continuing operations $ 1.15 $ 0.83 Loss from discontinued operations (0.03 ) (0.01 ) Net income attributable to common stockholders $ 1.12 $ 0.82 (1) The reallocation adjustment for participating securities to arrive at the numerator to calculate diluted EPS was $0.1 million for the three months ended March 31, 2018 . (2) The two-class method assumes that participating securities are not exercised or converted. As such, weighted average diluted shares outstanding excluded 8.4 million shares related to the participating securities for the three months ended March 31, 2018 . As of January 31, 2018, all 30.0 million shares of convertible preferred stock issued upon the Company’s emergence from the Chapter 11 reorganization had been converted into 59.3 million shares of common stock, which is inclusive of the shares that had been issued for the payable in-kind preferred stock dividends.

Financial Instruments and Other

Financial Instruments and Other Guarantees	3 Months Ended
	Mar. 31, 2019
Financial Instruments And Guarantees With Off Balance Sheet Risk Disclosure [Abstract]
Financial Instruments and Other Guarantees	Financial Instruments and Other Guarantees In the normal course of business, the Company is a party to various guarantees and financial instruments that carry off-balance-sheet risk and are not reflected in the accompanying condensed consolidated balance sheets. At March 31, 2019 , such instruments included $1,571.3 million of surety bonds and $239.6 million of letters of credit. Such financial instruments provide support for the Company’s reclamation bonding requirements, lease obligations, insurance policies and various other performance guarantees. The Company periodically evaluates the instruments for on-balance-sheet treatment based on the amount of exposure under the instrument and the likelihood of required performance. The Company does not expect any material losses to result from these guarantees or off-balance-sheet instruments in excess of liabilities provided for in the accompanying condensed consolidated balance sheets. The Company is required to provide various forms of financial assurance in support of its mining reclamation obligations in the jurisdictions in which it operates. Such requirements are typically established by statute or under mining permits. At March 31, 2019 , the Company’s mining reclamation obligations of $755.7 million were supported by surety bonds of $1,358.9 million , as well as letters of credit issued under the Company’s receivables securitization program and Revolver amounting to $147.3 million . Accounts Receivable Securitization The Company entered into the Sixth Amended and Restated Receivables Purchase Agreement, as amended, dated as of April 3, 2017 (the Receivables Purchase Agreement) to extend the Company’s receivables securitization facility previously in place and expand that facility to include certain receivables from the Company’s Australian operations. The receivables securitization program (Securitization Program) is subject to certain liquidity requirements and other customary events of default set forth in the Receivables Purchase Agreement. The Securitization Program provides for up to $250.0 million in funding accounted for as a secured borrowing, limited to the availability of eligible receivables, and may be secured by a combination of collateral and the trade receivables underlying the program, from time to time. Funding capacity under the Securitization Program may also be utilized for letters of credit in support of other obligations. During 2019, the Company entered into an amendment to the Securitization Program to extend its term through April 1, 2022 and reduce program fees. Under the terms of the Securitization Program, the Company contributes the trade receivables of its participating subsidiaries on a revolving basis to P&L Receivables, its wholly-owned, bankruptcy-remote subsidiary, which then sells the receivables to unaffiliated banks. P&L Receivables retains the ability to repurchase the receivables in certain circumstances. The assets and liabilities of P&L Receivables are consolidated with Peabody, and the Securitization Program is treated as a secured borrowing for accounting purposes, but the assets of P&L Receivables will be used first to satisfy the creditors of P&L Receivables, not Peabody’s creditors. The borrowings under the Securitization Program remain outstanding throughout the term of the agreement, subject to the Company maintaining sufficient eligible receivables, by continuing to contribute trade receivables to P&L Receivables, unless an event of default occurs. At March 31, 2019 , the Company had no outstanding borrowings and $131.7 million of letters of credit issued under the Securitization Program. The letters of credit were primarily in support of portions of the Company’s obligations for reclamation, workers’ compensation and postretirement benefits. The Company had no collateral requirement under the Securitization Program at March 31, 2019 or December 31, 2018 . The Company incurred fees associated with the Securitization Program of $1.1 million and $1.3 million during the three months ended March 31, 2019 and 2018 , respectively, which have been recorded as interest expense in the accompanying unaudited condensed consolidated statements of operations. Collateral Arrangements and Restricted Cash From time to time, the Company is required to remit cash to certain regulatory authorities and other third parties as collateral for financial assurances associated with a variety of long-term obligations and commitments surrounding the mining, reclamation and shipping of its production. During the three months ended March 31, 2018 , $254.1 million of such collateral and other restricted cash was returned to the Company, largely as the result of replacing collateral balances with third-party surety bonding in Australia. Other The Company has provided financial guarantees under certain long-term debt agreements entered into by its subsidiaries and substantially all of the Company’s U.S. subsidiaries provide financial guarantees under long-term debt agreements entered into by the Company. The maximum amounts payable under the Company’s debt agreements are equal to the respective principal and interest payments.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments Unconditional Purchase Obligations As of March 31, 2019 , purchase commitments for capital expenditures were $134.6 million , all of which is obligated within the next 12 months. There were no other material changes to the Company’s commitments from the information provided in Note 26. “Commitments and Contingencies” to the consolidated financial statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 . Contingencies From time to time, the Company or its subsidiaries are involved in legal proceedings arising in the ordinary course of business or related to indemnities or historical operations. The Company believes it has recorded adequate reserves for these liabilities. The Company discusses its significant legal proceedings below, including ongoing proceedings and those that impacted the Company’s results of operations for the periods presented. Litigation Relating to the Chapter 11 Cases Ad Hoc Committee . A group of creditors (the Ad Hoc Committee) that held certain interests in the Company's prepetition indebtedness appealed the Bankruptcy Court’s order confirming the Company’s plan of reorganization (the Plan). On December 29, 2017, the United States District Court for the Eastern District of Missouri (the District Court) entered an order dismissing the Ad Hoc Committee's appeal, and, in the alternative, affirming the order confirming the Plan. On January 26, 2018, the Ad Hoc Committee appealed the District Court's order to the United States Court of Appeals for the Eighth Circuit (the Eighth Circuit). In its appeal, the Ad Hoc Committee does not ask the Eighth Circuit to reverse the order confirming the Plan. Instead, the Ad Hoc Committee asks the Eighth Circuit to award the Ad Hoc Committee members either unspecified damages or the right to buy an unspecified amount of Company stock at a discount. Oral argument on the appeal was held April 16, 2019, and the Eighth Circuit panel reserved decision and took the case under submission. The Company does not believe the appeal is meritorious and will vigorously defend against the Ad Hoc Committee’s claims. Litigation Relating to Continuing Operations Peabody Monto Coal Pty Ltd, Monto Coal 2 Pty Ltd and Peabody Energy Australia PCI Pty Ltd (PEA-PCI). In October 2007, a claim was made against Peabody Monto Coal Pty Ltd, a wholly-owned subsidiary, and Monto Coal 2 Pty Ltd, an equity accounted investee of Macarthur Coal Limited (Macarthur), now known as PEA-PCI. The claim alleged that the Macarthur companies breached certain agreements by failing to develop a mine project. The claim was amended to assert that Macarthur induced the alleged breach of the Monto Coal Joint Venture Agreement. The Company acquired Macarthur and its subsidiaries in 2011. These claims, which are pending before the Supreme Court of Queensland, Australia, seek damages of up to $1.1 billion Australian dollars, plus interest and costs. The Company asserts that the Macarthur companies were never under an obligation to develop the mine project because the project was not economically viable. The Company disputes all of the claims brought by the plaintiffs and is vigorously defending its position. The trial commenced on April 8, 2019. Berenergy Corporation. The Company has been in a legal dispute with Berenergy Corporation (Berenergy) regarding Berenergy’s access to certain of its underground oil deposits beneath the Company’s North Antelope Rochelle Mine and contiguous undisturbed areas. Berenergy contends the Company should not be able to mine the area where Berenergy and Peabody hold conflicting leases. Berenergy also contends that if the Company does mine the area, then the Company should be liable to Berenergy for the cost of certain special procedures and equipment required to access the secondary deposits remotely from outside the Company’s mine area, which has been estimated at $13.1 million by Berenergy. The Company believes that it should be allowed to mine the area conflicting with Berenergy’s leases so long as it pays for the reasonable value of the oil reserves under Berenergy’s wells that sit on its four leases, which the Company estimates to be approximately $1.0 million . The parties entered into an interim agreement that allows Peabody to plug certain of Berenergy’s wells to allow Peabody to mine certain areas where the two parties hold conflicting leases. This dispute currently has proceedings before the Wyoming Supreme Court and a federal court in Wyoming. The Company will vigorously defend its position in both proceedings, as it believes Berenergy’s claims are without merit and that the likelihood of a material loss resulting from the matter is remote. County of San Mateo, County of Marin, City of Imperial Beach. The Company was named as a defendant, along with numerous other companies, in three nearly identical lawsuits. The lawsuits seek to hold a wide variety of companies that produce fossil fuels liable for the alleged impacts of the greenhouse gas emissions attributable to those fuels. The lawsuits primarily assert that the companies’ products have caused a sea level rise that is damaging the plaintiffs. The complaints specifically alleged that the defendants’ activities from 1965 to 2015 caused such damage. The Company filed a motion to enforce the Plan because it enjoins claims that arose before the effective date of the Plan. The motion to enforce was granted on October 24, 2017, and the Bankruptcy Court ordered the plaintiffs to dismiss their lawsuits against the Company. On November 26, 2017, the plaintiffs appealed the Bankruptcy Court’s October 24, 2017 order to the District Court. On November 28, 2017, plaintiffs sought a stay pending appeal from the Bankruptcy Court, which was denied December 8, 2017. On December 19, 2017, the plaintiffs moved the District Court for a stay pending appeal. The District Court denied the stay request on September 20, 2018, and the plaintiffs have appealed that decision to the U.S. Court of Appeals from the Eighth Circuit. On March 29, 2019, the District Court affirmed the Bankruptcy Court ruling enjoining the plaintiffs from proceeding with their lawsuits against the Company. That ruling likewise is being appealed. In the underlying cases pending in California, the U.S. District Court for the Northern District of California granted plaintiffs’ motion for remand and decided the cases should be heard in state court. The defendants appealed the order granting remand to the Ninth Circuit and sought a stay of the U.S. District Court for the Northern District of California decision pending completion of the Ninth Circuit appeal. The U.S. District Court for the Northern District of California granted defendants’ request for a stay pending completion of the Ninth Circuit appeal. The plaintiffs filed a motion to dismiss part of the appeal. The parties are now litigating at the Ninth Circuit whether a state or federal court should hear these lawsuits. Regardless of whether state court or federal court is the venue, the Company believes the lawsuits against it should be dismissed under enforcement of the Plan. The Company does not believe the lawsuits are meritorious and, if the lawsuits are not dismissed, the Company intends to vigorously defend them. 10th Circuit U.S. Bureau of Land Management (BLM) Appeal. On September 15, 2017, the Tenth Circuit Court of Appeals reversed the District Court of Wyoming’s decision upholding BLM’s approval of four coal leases in the Powder River Basin. Two of the four leases relate to the Company’s North Antelope Rochelle Mine in Wyoming. There is no immediate impact on the Company’s leases as the Court of Appeals did not vacate the leases as part of its ruling. Rather, the Court of Appeals remanded the case back to the District Court of Wyoming with directions to order BLM to revise its environmental analysis. On November 27, 2017, the District Court of Wyoming ordered BLM to revise its environmental analysis. BLM published its draft environmental analysis on July 30, 2018. The Company, along with the National Mining Association, the Wyoming Mining Association and Arch Coal, Inc., submitted comments on the draft environmental analysis by the comment deadline of October 4, 2018. BLM’s recent status report filed with the District Court of Wyoming indicated it would not issue a final environmental analysis until June 2019 and will refine that estimate in a future report. The Company’s operations will continue in the normal course during this period since the decision has no impact on mining at this time. The Company currently believes that its operations are unlikely to be materially impacted by this case, but the timing and magnitude of any impact on the Company’s future operations is not certain. Central Arizona Water Conservation District (CAWCD). On May 1, 2018, the Company, along with the Hopi Tribe and the UMWA, filed a lawsuit against the CAWCD. CAWCD operates, on behalf of the Bureau of Reclamation, the Central Arizona Project (CAP), an aqueduct system that brings water from the Colorado River to three counties in Arizona. CAWCD historically obtained most of CAP’s power requirements from the Navajo Generating Station (NGS), which is served by a single Peabody mine. NGS is owned by several private companies and one governmental entity. The owners of NGS issued a statement that they do not currently intend to be the operators of the plant beyond December 2019. Recently, CAWCD made the decision to obtain a portion of CAP’s power requirements from sources other than NGS for 2020 and thereafter. The lawsuit seeks a determination that federal law requires CAWCD to obtain CAP’s power requirements from NGS. A motion to dismiss filed by CAWCD was granted on April 1, 2019. The court provided the Company with leave to file an amended complaint, but at this time, the Company does not anticipate doing so. Other At times the Company becomes a party to other disputes, including those related to contract miner performance, claims, lawsuits, arbitration proceedings, regulatory investigations and administrative procedures in the ordinary course of business in the U.S., Australia and other countries where the Company does business. Based on current information, the Company believes that such other pending or threatened proceedings are likely to be resolved without a material adverse effect on its financial condition, results of operations or cash flows.

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2019
Segment Reporting [Abstract]
Segment Information	Segment Information The Company reports its results of operations through the following reportable segments: Seaborne Thermal Mining, Seaborne Metallurgical Mining, Powder River Basin Mining, Midwestern U.S. Mining, Western U.S. Mining and Corporate and Other. The Company’s chief operating decision maker uses Adjusted EBITDA as the primary metric to measure the segments’ operating performance. Adjusted EBITDA is a non-GAAP financial measure defined as income from continuing operations before deducting net interest expense, income taxes, asset retirement obligation expenses, depreciation, depletion and amortization and reorganization items, net. Adjusted EBITDA is also adjusted for the discrete items that management excluded in analyzing the segments’ operating performance, as displayed in the reconciliation below. Management believes non-GAAP performance measures are used by investors to measure the Company’s operating performance and lenders to measure the Company’s ability to incur and service debt. Adjusted EBITDA is not intended to serve as an alternative to U.S. GAAP measures of performance and may not be comparable to similarly-titled measures presented by other companies. Reportable segment results were as follows: Three Months Ended March 31, 2019 2018 (Dollars in millions) Revenues: Seaborne Thermal Mining $ 251.0 $ 201.4 Seaborne Metallurgical Mining 324.5 466.2 Powder River Basin Mining 287.3 389.3 Midwestern U.S. Mining 179.1 201.7 Western U.S. Mining 155.7 143.7 Corporate and Other 53.0 60.4 Total $ 1,250.6 $ 1,462.7 Adjusted EBITDA: Seaborne Thermal Mining $ 94.7 $ 61.6 Seaborne Metallurgical Mining 85.8 166.4 Powder River Basin Mining 36.4 74.5 Midwestern U.S. Mining 33.3 31.2 Western U.S. Mining 42.6 32.0 Corporate and Other (1) (38.9 ) (1.8 ) Total $ 253.9 $ 363.9 (1) As described in Note 16. “Other Events,” included in the three months ended March 31, 2018, is the gain of $20.6 million recognized on the sale of certain surplus land assets in Queensland and the gain of $7.1 million recognized on the sale of the Company’s interest in the RMJV. A reconciliation of consolidated income from continuing operations, net of income taxes to Adjusted EBITDA follows: Three Months Ended March 31, 2019 2018 (Dollars in millions) Income from continuing operations, net of income taxes $ 133.3 $ 208.3 Depreciation, depletion and amortization 172.5 169.6 Asset retirement obligation expenses 13.8 12.3 Provision for North Goonyella equipment loss 24.7 — North Goonyella insurance recoveries - equipment (1) (91.1 ) — Changes in deferred tax asset valuation allowance and reserves and amortization of basis difference related to equity affiliates — (7.6 ) Interest expense 35.8 36.3 Interest income (8.3 ) (7.2 ) Reorganization items, net — (12.8 ) Unrealized gains on economic hedges (39.8 ) (38.6 ) Unrealized (gains) losses on non-coal trading derivative contracts (0.2 ) 1.8 Fresh start take-or-pay contract-based intangible recognition (5.6 ) (8.3 ) Income tax provision 18.8 10.1 Total Adjusted EBITDA $ 253.9 $ 363.9 (1) As described in Note 16. “Other Events,” the Company recorded a $125.0 million insurance recovery during the three months ended March 31, 2019 related to losses incurred at its North Goonyella Mine. Of this amount, Adjusted EBITDA excludes an allocated amount applicable to total equipment losses recognized at the time of the insurance recovery settlement, which consisted of $24.7 million and $66.4 million recognized during the three months ended March 31, 2019 and the year ended December 31, 2018, respectively. The remaining $33.9 million , applicable to incremental costs and business interruption losses, is included in Adjusted EBITDA for the three months ended March 31, 2019.

Derivatives and Fair Value Me_2

Derivatives and Fair Value Measurements (Policies)	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Corporate Hedging - Coal Trading [Policy Text Block]	The Company’s risk management function, which is independent of the Company’s coal trading function, is responsible for valuation policies and procedures, with oversight from executive management. Generally, the Company’s Level 3 instruments or contracts are valued using bid/ask price quotations and other market assessments obtained from multiple, independent third-party brokers or other transactional data incorporated into internally-generated discounted cash flow models. Decreases in the number of third-party brokers or market liquidity could erode the quality of market information and therefore the valuation of the Company’s market positions. The Company’s valuation techniques include basis adjustments to the foregoing price inputs for quality, such as sulfur and ash content, location differentials, expressed as port and freight costs, and credit risk. The Company’s risk management function independently validates the Company’s valuation inputs, including unobservable inputs, with third-party information and settlement prices from other sources where available. A daily process is performed to analyze market price changes and changes to the portfolio. Further periodic validation occurs at the time contracts are settled with the counterparty. These valuation techniques have been consistently applied in all periods presented, and the Company believes it has obtained the most accurate information available for the types of derivative contracts held.

Leases (Policies)

Leases (Policies)	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Lessee, Leases [Policy Text Block]	The Company determines if an arrangement is a lease at inception. ROU assets represent the Company's right to use an underlying asset for the lease term and lease liabilities represent its obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. For the purpose of calculating such present values, lease payments include components that vary based upon an index or rate, using the prevailing index or rate at the commencement date, and exclude components that vary based upon other factors. As most of its leases do not provide an implicit rate, the Company uses its incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. The Company's leases may include options to extend or terminate the lease, and such options are reflected in the term when their exercise is reasonably certain. Lease expense is recognized on a straight-line basis over the lease term. For certain equipment leases, the Company applies a portfolio approach to effectively account for the operating lease ROU assets and liabilities.

Newly Adopted Accounting Stan_2

Newly Adopted Accounting Standards and Accounting Standards Not Yet Implemented Newly Adopted Accounting Standards and Accounting Standards Not Yet Implemented (Tables)	3 Months Ended
	Mar. 31, 2019
Newly Adopted Accounting Standards and Accounting Standards Not Yet Implemented [Abstract]
Schedule of Adjustments Due to ASU 2014-09 [Table Text Block]	The most significant impact was the recognition of ROU assets and lease liabilities for operating leases upon adoption, as set forth in the table below. The Company's accounting for finance leases remained unchanged. Adoption of ASU 2016-02 January 1, 2019 (Dollars in millions) ASSETS Operating lease right-of-use assets $ 109.3 Total assets $ 109.3 LIABILITIES Accounts payable and accrued expenses $ 41.8 Total current liabilities 41.8 Operating lease liabilities, less current portion 67.5 Total liabilities $ 109.3

Acquisition of Shoal Creek Mi_2

Acquisition of Shoal Creek Mine (Tables)	3 Months Ended
	Mar. 31, 2019
Acquisition of Shoal Creek Mine [Abstract]
Schedule of Business Acquisitions, by Acquisition [Table Text Block]	The following table summarizes the preliminary estimated fair values of assets acquired and liabilities assumed that were recognized at the acquisition and control date (in millions): Inventories $ 39.7 Property, plant, equipment and mine development 364.7 Current liabilities (4.1 ) Asset retirement obligations (10.5 ) Total purchase price $ 389.8
Business Acquisition, Pro Forma Information [Table Text Block]	The unaudited pro forma financial information does not necessarily reflect the results of operations that would have occurred had the operations of the Company and Shoal Creek Mine been combined during those periods or that may be attained in the future. Three Months Ended March, 31, 2018 (Dollars in millions, except per share data) Revenues $ 1,567.7 Income from continuing operations, net of income taxes 251.2 Basic earnings per share from continuing operations $ 1.17 Diluted earnings per share from continuing operations $ 1.15

Revenues (Tables)

Revenues (Tables)	3 Months Ended
	Mar. 31, 2019
Revenue Recognition [Abstract]
Disaggregation of Revenue by Product Type and Market [Table Text Block]	With respect to its seaborne mining segments, the Company classifies as “Export” certain revenue from domestically-delivered coal under contracts in which the price is derived on a basis similar to export contracts. Three Months Ended March 31, 2019 Seaborne Thermal Mining Seaborne Metallurgical Mining Powder River Basin Mining Midwestern U.S. Mining Western U.S. Mining Corporate and Other (1) Consolidated (Dollars in millions) Thermal coal Domestic $ 38.4 $ — $ 287.3 $ 179.0 $ 142.7 $ — $ 647.4 Export 211.9 — — — 7.0 — 218.9 Total thermal 250.3 — 287.3 179.0 149.7 — 866.3 Metallurgical coal Export — 323.7 — — — — 323.7 Total metallurgical — 323.7 — — — — 323.7 Other 0.7 0.8 — 0.1 6.0 53.0 60.6 Revenues $ 251.0 $ 324.5 $ 287.3 $ 179.1 $ 155.7 $ 53.0 $ 1,250.6 Three Months Ended March 31, 2018 Seaborne Thermal Mining Seaborne Metallurgical Mining Powder River Basin Mining Midwestern U.S. Mining Western U.S. Mining Corporate and Other (1) Consolidated (Dollars in millions) Thermal coal Domestic $ 36.1 $ — $ 389.2 $ 200.9 $ 130.3 $ — $ 756.5 Export 164.9 — — 0.7 8.0 — 173.6 Total thermal 201.0 — 389.2 201.6 138.3 — 930.1 Metallurgical coal Export — 465.3 — — — — 465.3 Total metallurgical — 465.3 — — — — 465.3 Other 0.4 0.9 0.1 0.1 5.4 60.4 67.3 Revenues $ 201.4 $ 466.2 $ 389.3 $ 201.7 $ 143.7 $ 60.4 $ 1,462.7
Disaggregation of Revenue by Contract Duration [Table Text Block]	Revenue by contract duration was as follows: Three Months Ended March 31, 2019 Seaborne Thermal Mining Seaborne Metallurgical Mining Powder River Basin Mining Midwestern U.S. Mining Western U.S. Mining Corporate and Other (1) Consolidated (Dollars in millions) One year or longer $ 171.1 $ 232.8 $ 280.1 $ 167.8 $ 146.0 $ — $ 997.8 Less than one year 79.2 90.9 7.2 11.2 3.7 — 192.2 Other (2) 0.7 0.8 — 0.1 6.0 53.0 60.6 Revenues $ 251.0 $ 324.5 $ 287.3 $ 179.1 $ 155.7 $ 53.0 $ 1,250.6 Three Months Ended March 31, 2018 Seaborne Thermal Mining Seaborne Metallurgical Mining Powder River Basin Mining Midwestern U.S. Mining Western U.S. Mining Corporate and Other (1) Consolidated (Dollars in millions) One year or longer $ 177.3 $ 397.5 $ 343.4 $ 187.6 $ 127.3 $ — $ 1,233.1 Less than one year 23.7 67.8 45.8 14.0 11.0 — 162.3 Other (2) 0.4 0.9 0.1 0.1 5.4 60.4 67.3 Revenues $ 201.4 $ 466.2 $ 389.3 $ 201.7 $ 143.7 $ 60.4 $ 1,462.7 (1) Corporate and Other revenue includes realized and unrealized gains and losses related to mark-to-market activity from economic hedge activities intended to hedge future coal sales. Refer to Note 8. “Derivatives and Fair Value Measurements” for additional information regarding the economic hedge activities. (2) Other includes revenues from arrangements such as customer contract-related payments, royalties related to coal lease agreements, sales agency commissions, farm income and property and facility rentals, for which contract duration is not meaningful.
Schedule of Accounts Receivable [Table Text Block]	“Accounts receivable, net” at March 31, 2019 and December 31, 2018 consisted of the following: March 31, 2019 December 31, 2018 (Dollars in millions) Trade receivables, net $ 366.6 $ 345.5 Miscellaneous receivables, net 188.0 104.9 Accounts receivable, net $ 554.6 $ 450.4

Discontinued Operations (Tables

Discontinued Operations (Tables)	3 Months Ended
	Mar. 31, 2019
Discontinued Operations and Disposal Groups [Abstract]
Summarized results of discontinued operations	Results from discontinued operations were as follows during the periods presented below: Three Months Ended March 31, 2019 2018 (Dollars in millions) Loss from discontinued operations, net of income taxes $ (3.4 ) $ (1.3 ) Liabilities of Discontinued Operations Liabilities classified as discontinued operations included in the Company’s condensed consolidated balance sheets were as follows: March 31, 2019 December 31, 2018 (Dollars in millions) Liabilities: Accounts payable and accrued expenses $ 54.0 $ 54.0 Other noncurrent liabilities 141.3 141.0 Total liabilities classified as discontinued operations $ 195.3 $ 195.0

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Mar. 31, 2019
Inventory Disclosure [Abstract]
Inventories	Inventories as of March 31, 2019 and December 31, 2018 consisted of the following: March 31, 2019 December 31, 2018 (Dollars in millions) Materials and supplies $ 118.9 $ 118.1 Raw coal 50.0 53.6 Saleable coal 99.6 108.5 Total $ 268.5 $ 280.2

Equity Method Investments Finan

Equity Method Investments Financing Receivables (Tables)	3 Months Ended
	Mar. 31, 2019
Financing Receivables [Abstract]
Equity Method Investments [Table Text Block]	Middlemount’s standalone results include (on a 50% attributable basis): Three Months Ended March 31, 2019 2018 (Dollars in millions) Depreciation, depletion and amortization and asset retirement obligation expenses $ 3.6 $ 3.9 Net interest expense 2.2 3.6 Income tax provision 1.7 5.1

Derivatives and Fair Value Me_3

Derivatives and Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value, by Balance Sheet Grouping [Table Text Block]	The fair value of derivatives reflected in the accompanying condensed consolidated balance sheets are set forth in the table below. March 31, 2019 December 31, 2018 Asset Derivative Liability Derivative Asset Derivative Liability Derivative (Dollars in millions) Foreign currency option contracts $ 1.3 $ — $ 1.2 $ — Coal contracts related to forecasted sales 23.0 (7.9 ) 6.6 (23.1 ) Coal trading contracts 144.9 (137.7 ) 59.7 (64.4 ) Total derivatives 169.2 (145.6 ) 67.5 (87.5 ) Effect of counterparty netting (145.5 ) 145.5 (64.5 ) 64.5 Variation margin (held) posted (18.2 ) — — 21.8 Net derivatives and margin as classified in the balance sheets $ 5.5 $ (0.1 ) $ 3.0 $ (1.2 )
Derivative Instruments, Gain (Loss) [Table Text Block]	The tables below show the amounts of pre-tax gains and losses related to the Company’s derivatives. Three Months Ended March 31, 2019 Total (loss) gain recognized in income (Loss) gain realized in income on derivatives Unrealized (loss) gain recognized in income on derivatives Financial Instrument (Dollars in millions) Foreign currency option contracts $ (1.1 ) $ (1.3 ) $ 0.2 Coal contracts related to forecasted sales 50.7 10.9 39.8 Coal trading contracts (1.1 ) (4.8 ) 3.7 Total $ 48.5 $ 4.8 $ 43.7 Three Months Ended March 31, 2018 Total (loss) gain recognized in income (Loss) gain realized in income on derivatives Unrealized (loss) gain recognized in income on derivatives Financial Instrument (Dollars in millions) Foreign currency option contracts $ (4.2 ) $ (2.4 ) $ (1.8 ) Coal contracts related to forecasted sales 59.8 21.2 38.6 Coal trading contracts (1.0 ) (2.8 ) 1.8 Total $ 54.6 $ 16.0 $ 38.6
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	The following tables set forth the hierarchy of the Company’s net financial asset positions for which fair value is measured on a recurring basis: March 31, 2019 Level 1 Level 2 Level 3 Total (Dollars in millions) Foreign currency option contracts $ — $ 1.3 $ — $ 1.3 Coal contracts related to forecasted sales — 18.8 — 18.8 Coal trading contracts — (14.7 ) — (14.7 ) Equity securities — — 10.0 10.0 Total net financial assets $ — $ 5.4 $ 10.0 $ 15.4 December 31, 2018 Level 1 Level 2 Level 3 Total (Dollars in millions) Foreign currency option contracts $ — $ 1.2 $ — $ 1.2 Coal contracts related to forecasted sales — (21.2 ) — (21.2 ) Coal trading contracts — 21.8 — 21.8 Equity securities — — 10.0 10.0 Total net financial assets $ — $ 1.8 $ 10.0 $ 11.8
Carrying Amounts And Estimated Fair Values Of Companys Debt [Table Text Block]	The carrying amount and estimated fair values of the Company’s current and long-term debt as of March 31, 2019 and December 31, 2018 are summarized as follows: March 31, 2019 December 31, 2018 Carrying Estimated Carrying Estimated (Dollars in millions) Current and Long-term debt $ 1,361.7 $ 1,406.6 $ 1,367.0 $ 1,366.2

Intangible Contract Assets an_2

Intangible Contract Assets and Liabilities (Tables)	3 Months Ended
	Mar. 31, 2019
Revenue Recognition [Abstract]
Schedule Of Intangible Assets And Liabilities	The balances, net of accumulated amortization, and respective balance sheet classifications at March 31, 2019 and December 31, 2018 , are set forth in the following tables: March 31, 2019 (Dollars in millions) Assets Liabilities Net Total Coal supply agreements $ 60.5 $ (27.3 ) $ 33.2 Take-or-pay contracts — (51.8 ) (51.8 ) Total $ 60.5 $ (79.1 ) $ (18.6 ) Balance sheet classification: Investments and other assets $ 60.5 $ — $ 60.5 Accounts payable and accrued expenses — (14.0 ) (14.0 ) Other noncurrent liabilities — (65.1 ) (65.1 ) Total $ 60.5 $ (79.1 ) $ (18.6 ) December 31, 2018 (Dollars in millions) Assets Liabilities Net Total Coal supply agreements $ 70.9 $ (32.9 ) $ 38.0 Take-or-pay contracts — (57.1 ) (57.1 ) Total $ 70.9 $ (90.0 ) $ (19.1 ) Balance sheet classification: Investments and other assets $ 70.9 $ — $ 70.9 Accounts payable and accrued expenses — (20.3 ) (20.3 ) Other noncurrent liabilities — (69.7 ) (69.7 ) Total $ 70.9 $ (90.0 ) $ (19.1 )

Property, Plant, Equipment an_2

Property, Plant, Equipment and Mine Development (Tables)	3 Months Ended
	Mar. 31, 2019
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	The composition of property, plant, equipment and mine development, net, as of March 31, 2019 and December 31, 2018 is set forth in the table below: March 31, 2019 December 31, 2018 (Dollars in millions) Land and coal interests $ 4,149.8 $ 4,148.8 Buildings and improvements 558.3 559.3 Machinery and equipment 1,474.0 1,456.3 Less: Accumulated depreciation, depletion and amortization (1,112.6 ) (957.4 ) Property, plant, equipment and mine development, net $ 5,069.5 $ 5,207.0

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Lease, Cost [Table Text Block]	The components of lease expense during the three months ended March 31, 2019 were as follows: Three Months Ended March 31, 2019 (Dollars in millions) Operating lease cost: Operating lease cost $ 15.5 Short-term lease cost 8.3 Variable lease cost 6.0 Sublease income (1.4 ) Total operating lease cost $ 28.4 Finance lease cost: Amortization of right-of-use assets $ 4.1 Interest on lease liabilities 0.5 Total finance lease cost $ 4.6
Schedule of Supplemental Balance Sheet Information Related to Leases [Table Text Block]	Supplemental balance sheet information related to leases at March 31, 2019 was as follows: March 31, 2019 (Dollars in millions) Operating leases: Operating lease right-of-use assets $ 97.0 Accounts payable and accrued expenses $ 30.7 Operating lease liabilities, less current portion 58.2 Total operating lease liabilities $ 88.9 Finance leases: Property, plant, equipment and mine development $ 97.8 Accumulated depreciation (33.4 ) Property, plant, equipment and mine development, net $ 64.4 Current portion of long-term debt $ 30.8 Long-term debt, less current portion 1.9 Total finance lease liabilities $ 32.7 Weighted average remaining lease term Operating leases 4.2 years Finance leases 5.4 years Weighted average discount rate Operating leases 7.4 % Finance leases 7.6 %
Schedule of Supplemental Cash Flow Information Related to Leases [Table Text Block]	Supplemental cash flow information related to leases during the three months ended March 31, 2019 was as follows: Three Months Ended March 31, 2019 (Dollars in millions) Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows for operating leases $ 24.1 Operating cash flows for finance leases 0.7 Financing cash flows for finance leases 7.3 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 0.5 Finance leases —
Schedule of Maturities of Operating and Finance Lease Liabilities [Table Text Block]	Maturities of lease liabilities were as follows: Period Ending December 31, Operating Leases Finance Leases (Dollars in millions) 2019 $ 27.0 $ 28.7 2020 28.0 8.1 2021 16.5 0.5 2022 11.9 0.5 2023 12.2 0.5 2024 and thereafter 12.1 8.7 Total lease payments 107.7 47.0 Less imputed interest (18.8 ) (14.3 ) Total lease liabilities $ 88.9 $ 32.7

Long-term Debt (Tables)

Long-term Debt (Tables)	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	The Company’s total indebtedness as of March 31, 2019 and December 31, 2018 consisted of the following: March 31, 2019 December 31, 2018 (Dollars in millions) 6.000% Senior Secured Notes due March 2022 $ 500.0 $ 500.0 6.375% Senior Secured Notes due March 2025 500.0 500.0 Senior Secured Term Loan due 2025, net of original issue discount 395.0 395.9 Finance lease and other obligations 32.7 40.0 Less: Debt issuance costs (66.0 ) (68.9 ) 1,361.7 1,367.0 Less: Current portion of long-term debt 34.8 36.5 Long-term debt $ 1,326.9 $ 1,330.5

Pension and Postretirement Be_2

Pension and Postretirement Benefit Costs (Tables)	3 Months Ended
	Mar. 31, 2019
Defined benefit pension plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Net Benefit Costs	Net periodic pension cost (benefit) included the following components: Three Months Ended March 31, 2019 2018 (Dollars in millions) Service cost for benefits earned $ 0.5 $ 0.6 Interest cost on projected benefit obligation 8.3 7.8 Expected return on plan assets (7.8 ) (10.7 ) Net periodic pension cost (benefit) $ 1.0 $ (2.3 )
Postretirement benefit plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Net Benefit Costs	Net periodic postretirement benefit cost included the following components: Three Months Ended March 31, 2019 2018 (Dollars in millions) Service cost for benefits earned $ 1.2 $ 2.0 Interest cost on accumulated postretirement benefit obligation 6.3 7.1 Expected return on plan assets (0.1 ) — Amortization of prior service credit (2.2 ) — Net periodic postretirement benefit cost $ 5.2 $ 9.1

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2019
Equity [Abstract]
After-tax components of comprehensive income (loss)	The following table sets forth the after-tax components of accumulated other comprehensive income and changes thereto recorded during the three months ended March 31, 2019 : Foreign Currency Translation Adjustment Prior Service Credit (Cost) Associated with Postretirement Plans Total Accumulated Other Comprehensive Income (Dollars in millions) December 31, 2018 $ (4.5 ) $ 44.6 $ 40.1 Reclassification from other comprehensive income to earnings — (2.2 ) (2.2 ) Current period change 0.1 — 0.1 March 31, 2019 $ (4.4 ) $ 42.4 $ 38.0

Earnings per Share (EPS) (Table

Earnings per Share (EPS) (Tables)	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Earnings allocation method utilized in the calculation of basic and diluted EPS	The following illustrates the earnings allocation method utilized in the calculation of basic and diluted EPS. Three Months Ended March 31, 2019 2018 (In millions, except per share data) EPS numerator: Income from continuing operations, net of income taxes $ 133.3 $ 208.3 Less: Series A Convertible Preferred Stock dividends — 102.5 Less: Net income (loss) attributable to noncontrolling in terests 5.7 (2.1 ) Income from continuing operations attributable to common stockholders, before allocation of earnings to participating securities 127.6 107.9 Less: Earnings allocated to participating securities — 6.0 Income from continuing operations attributable to common stockholders, after allocation of earnings to participating securities (1) 127.6 101.9 Loss from discontinued operations, net of income taxes (3.4 ) (1.3 ) Less: Loss from discontinued operations allocated to participating securities — (0.1 ) Loss from discontinued operations attributable to common stockholders, after allocation of earnings to participating securities (3.4 ) (1.2 ) Net income attributable to common stockholders, after allocation of earnings to participating securities (1) $ 124.2 $ 100.7 EPS denominator: Weighted average shares outstanding — basic 108.5 120.9 Impact of dilutive securities 2.0 2.3 Weighted average shares outstanding — diluted (2) 110.5 123.2 Basic EPS attributable to common stockholders: Income from continuing operations $ 1.18 $ 0.84 Loss from discontinued operations (0.04 ) (0.01 ) Net income attributable to common stockholders $ 1.14 $ 0.83 Diluted EPS attributable to common stockholders: Income from continuing operations $ 1.15 $ 0.83 Loss from discontinued operations (0.03 ) (0.01 ) Net income attributable to common stockholders $ 1.12 $ 0.82 (1) The reallocation adjustment for participating securities to arrive at the numerator to calculate diluted EPS was $0.1 million for the three months ended March 31, 2018 . (2) The two-class method assumes that participating securities are not exercised or converted. As such, weighted average diluted shares outstanding excluded 8.4 million shares related to the participating securities for the three months ended March 31, 2018

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2019
Segment Reporting [Abstract]
Reportable segment results	Reportable segment results were as follows: Three Months Ended March 31, 2019 2018 (Dollars in millions) Revenues: Seaborne Thermal Mining $ 251.0 $ 201.4 Seaborne Metallurgical Mining 324.5 466.2 Powder River Basin Mining 287.3 389.3 Midwestern U.S. Mining 179.1 201.7 Western U.S. Mining 155.7 143.7 Corporate and Other 53.0 60.4 Total $ 1,250.6 $ 1,462.7 Adjusted EBITDA: Seaborne Thermal Mining $ 94.7 $ 61.6 Seaborne Metallurgical Mining 85.8 166.4 Powder River Basin Mining 36.4 74.5 Midwestern U.S. Mining 33.3 31.2 Western U.S. Mining 42.6 32.0 Corporate and Other (1) (38.9 ) (1.8 ) Total $ 253.9 $ 363.9 (1) As described in Note 16. “Other Events,” included in the three months ended March 31, 2018, is the gain of $20.6 million recognized on the sale of certain surplus land assets in Queensland and the gain of $7.1 million recognized on the sale of the Company’s interest in the RMJV.
Reconciliation of Adjusted EBITDA to consolidated loss from continuing operations, net of income taxes	A reconciliation of consolidated income from continuing operations, net of income taxes to Adjusted EBITDA follows: Three Months Ended March 31, 2019 2018 (Dollars in millions) Income from continuing operations, net of income taxes $ 133.3 $ 208.3 Depreciation, depletion and amortization 172.5 169.6 Asset retirement obligation expenses 13.8 12.3 Provision for North Goonyella equipment loss 24.7 — North Goonyella insurance recoveries - equipment (1) (91.1 ) — Changes in deferred tax asset valuation allowance and reserves and amortization of basis difference related to equity affiliates — (7.6 ) Interest expense 35.8 36.3 Interest income (8.3 ) (7.2 ) Reorganization items, net — (12.8 ) Unrealized gains on economic hedges (39.8 ) (38.6 ) Unrealized (gains) losses on non-coal trading derivative contracts (0.2 ) 1.8 Fresh start take-or-pay contract-based intangible recognition (5.6 ) (8.3 ) Income tax provision 18.8 10.1 Total Adjusted EBITDA $ 253.9 $ 363.9 (1) As described in Note 16. “Other Events,” the Company recorded a $125.0 million insurance recovery during the three months ended March 31, 2019 related to losses incurred at its North Goonyella Mine. Of this amount, Adjusted EBITDA excludes an allocated amount applicable to total equipment losses recognized at the time of the insurance recovery settlement, which consisted of $24.7 million and $66.4 million recognized during the three months ended March 31, 2019 and the year ended December 31, 2018, respectively. The remaining $33.9 million , applicable to incremental costs and business interruption losses, is included in Adjusted EBITDA for the three months ended March 31, 2019.

Basis of Presentation (Details)

Basis of Presentation (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Reorganization items, net	$ 0	$ (12.8)

Newly Adopted Accounting Stan_3

Newly Adopted Accounting Standards and Accounting Standards Not Yet Implemented - Adjustments Due to ASU 2016-02 (Details) - Accounting Standards Update 2016-02	Jan. 01, 2019
Operating lease right-of-use assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement	109.3
Total assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement	109.3
Current portion of operating lease liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement	41.8
Total current liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement	41.8
Operating lease liabilities, less current portion
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement	67.5
Total liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement	109.3

Acquisition of Shoal Creek Mi_3

Acquisition of Shoal Creek Mine - Purchase Accounting (Details) - Shoal Creek $ in Millions	Dec. 03, 2018USD ($)
Business Acquisition [Line Items]
Inventories	$ 39.7
Property, plant, equipment and mine development	364.7
Current liabilities	(4.1)
Asset retirement obligations	(10.5)
Total purchase price	$ 389.8

Acquisition of Shoal Creek Mi_4

Acquisition of Shoal Creek Mine - Pro Forma Financial Information (Details) - Shoal Creek $ / shares in Units, $ in Millions	9 Months Ended
	Dec. 31, 2017USD ($)$ / shares
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenue | $	$ 1,567.7
Income from continuing operations, net of income taxes | $	$ 251.2
Basic earnings per share from continuing operations | $ / shares	$ 1.17
Diluted earnings per share from continuing operations | $ / shares	$ 1.15

Acquisition of Shoal Creek Mi_5

Acquisition of Shoal Creek Mine - Textuals (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Feb. 22, 2019	Dec. 31, 2018	Dec. 03, 2018
Business Acquisition [Line Items]
Finite Lived Intangible Liabilities	$ 79.1			$ 90
Revenues	1,250.6	$ 1,462.7
Net income attributable to common stockholders	$ 124.2	$ 106.6
Shoal Creek
Business Acquisition [Line Items]
Working Capital Adjustment			$ 2.4
Finite Lived Intangible Liabilities					$ 3.5
Drummond Company, Inc.
Business Acquisition [Line Items]
Purchase price					$ 387.4

Revenues - Revenue by Product T

Revenues - Revenue by Product Type and Market (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 1,250.6	$ 1,462.7
Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	866.3	930.1
Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	323.7	465.3
Other
Disaggregation of Revenue [Line Items]
Revenues	60.6	67.3
Domestic | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	647.4	756.5
Export | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	218.9	173.6
Export | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	323.7	465.3
Seaborne Thermal Mining | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	251	201.4
Seaborne Thermal Mining | Operating Segments | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	250.3	201
Seaborne Thermal Mining | Operating Segments | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Seaborne Thermal Mining | Operating Segments | Other
Disaggregation of Revenue [Line Items]
Revenues	0.7	0.4
Seaborne Thermal Mining | Operating Segments | Domestic | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	38.4	36.1
Seaborne Thermal Mining | Operating Segments | Export | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	211.9	164.9
Seaborne Thermal Mining | Operating Segments | Export | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Seaborne Metallurgical Mining | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	324.5	466.2
Seaborne Metallurgical Mining | Operating Segments | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Seaborne Metallurgical Mining | Operating Segments | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	323.7	465.3
Seaborne Metallurgical Mining | Operating Segments | Other
Disaggregation of Revenue [Line Items]
Revenues	0.8	0.9
Seaborne Metallurgical Mining | Operating Segments | Domestic | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Seaborne Metallurgical Mining | Operating Segments | Export | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Seaborne Metallurgical Mining | Operating Segments | Export | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	323.7	465.3
Powder River Basin Mining | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	287.3	389.3
Powder River Basin Mining | Operating Segments | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	287.3	389.2
Powder River Basin Mining | Operating Segments | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Powder River Basin Mining | Operating Segments | Other
Disaggregation of Revenue [Line Items]
Revenues	0	0.1
Powder River Basin Mining | Operating Segments | Domestic | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	287.3	389.2
Powder River Basin Mining | Operating Segments | Export | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Powder River Basin Mining | Operating Segments | Export | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Midwestern U.S. Mining | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	179.1	201.7
Midwestern U.S. Mining | Operating Segments | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	179	201.6
Midwestern U.S. Mining | Operating Segments | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Midwestern U.S. Mining | Operating Segments | Other
Disaggregation of Revenue [Line Items]
Revenues	0.1	0.1
Midwestern U.S. Mining | Operating Segments | Domestic | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	179	200.9
Midwestern U.S. Mining | Operating Segments | Export | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	0	0.7
Midwestern U.S. Mining | Operating Segments | Export | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Western U.S. Mining | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	155.7	143.7
Western U.S. Mining | Operating Segments | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	149.7	138.3
Western U.S. Mining | Operating Segments | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Western U.S. Mining | Operating Segments | Other
Disaggregation of Revenue [Line Items]
Revenues	6	5.4
Western U.S. Mining | Operating Segments | Domestic | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	142.7	130.3
Western U.S. Mining | Operating Segments | Export | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	7	8
Western U.S. Mining | Operating Segments | Export | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Corporate and Other | Corporate, Non-Segment
Disaggregation of Revenue [Line Items]
Revenues	53	60.4
Corporate and Other | Corporate, Non-Segment | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Corporate and Other | Corporate, Non-Segment | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Corporate and Other | Corporate, Non-Segment | Other
Disaggregation of Revenue [Line Items]
Revenues	53	60.4
Corporate and Other | Corporate, Non-Segment | Domestic | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Corporate and Other | Corporate, Non-Segment | Export | Thermal coal
Disaggregation of Revenue [Line Items]
Revenues	0	0
Corporate and Other | Corporate, Non-Segment | Export | Metallurgical coal
Disaggregation of Revenue [Line Items]
Revenues	$ 0	$ 0

Revenues - Revenues by Contract

Revenues - Revenues by Contract Duration (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 1,250.6	$ 1,462.7
One year or longer
Disaggregation of Revenue [Line Items]
Revenues	997.8	1,233.1
Less than one year
Disaggregation of Revenue [Line Items]
Revenues	192.2	162.3
Other
Disaggregation of Revenue [Line Items]
Revenues	60.6	67.3
Seaborne Thermal Mining | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	251	201.4
Seaborne Thermal Mining | Operating Segments | One year or longer
Disaggregation of Revenue [Line Items]
Revenues	171.1	177.3
Seaborne Thermal Mining | Operating Segments | Less than one year
Disaggregation of Revenue [Line Items]
Revenues	79.2	23.7
Seaborne Thermal Mining | Operating Segments | Other
Disaggregation of Revenue [Line Items]
Revenues	0.7	0.4
Seaborne Metallurgical Mining | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	324.5	466.2
Seaborne Metallurgical Mining | Operating Segments | One year or longer
Disaggregation of Revenue [Line Items]
Revenues	232.8	397.5
Seaborne Metallurgical Mining | Operating Segments | Less than one year
Disaggregation of Revenue [Line Items]
Revenues	90.9	67.8
Seaborne Metallurgical Mining | Operating Segments | Other
Disaggregation of Revenue [Line Items]
Revenues	0.8	0.9
Powder River Basin Mining | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	287.3	389.3
Powder River Basin Mining | Operating Segments | One year or longer
Disaggregation of Revenue [Line Items]
Revenues	280.1	343.4
Powder River Basin Mining | Operating Segments | Less than one year
Disaggregation of Revenue [Line Items]
Revenues	7.2	45.8
Powder River Basin Mining | Operating Segments | Other
Disaggregation of Revenue [Line Items]
Revenues	0	0.1
Midwestern U.S. Mining | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	179.1	201.7
Midwestern U.S. Mining | Operating Segments | One year or longer
Disaggregation of Revenue [Line Items]
Revenues	167.8	187.6
Midwestern U.S. Mining | Operating Segments | Less than one year
Disaggregation of Revenue [Line Items]
Revenues	11.2	14
Midwestern U.S. Mining | Operating Segments | Other
Disaggregation of Revenue [Line Items]
Revenues	0.1	0.1
Western U.S. Mining | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	155.7	143.7
Western U.S. Mining | Operating Segments | One year or longer
Disaggregation of Revenue [Line Items]
Revenues	146	127.3
Western U.S. Mining | Operating Segments | Less than one year
Disaggregation of Revenue [Line Items]
Revenues	3.7	11
Western U.S. Mining | Operating Segments | Other
Disaggregation of Revenue [Line Items]
Revenues	6	5.4
Corporate and Other | Corporate, Non-Segment
Disaggregation of Revenue [Line Items]
Revenues	53	60.4
Corporate and Other | Corporate, Non-Segment | One year or longer
Disaggregation of Revenue [Line Items]
Revenues	0	0
Corporate and Other | Corporate, Non-Segment | Less than one year
Disaggregation of Revenue [Line Items]
Revenues	0	0
Corporate and Other | Corporate, Non-Segment | Other
Disaggregation of Revenue [Line Items]
Revenues	$ 53	$ 60.4

Revenues - Accounts Receivable

Revenues - Accounts Receivable (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Revenue Recognition [Abstract]
Trade receivables, net	$ 366.6	$ 345.5
Miscellaneous receivables, net	188	104.9
Accounts receivable, net	$ 554.6	$ 450.4

Revenues - Textuals (Details)

Revenues - Textuals (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2020	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Interest Income	$ 2.7	$ 2.1
Accounts Receivable [Member]
Disaggregation of Revenue [Line Items]
Allowance for Doubtful Accounts Receivable	0.1			$ 0.1
Provision for Doubtful Accounts	0	$ 0.2
Miscellaneous Receivables [Member]
Disaggregation of Revenue [Line Items]
Allowance for Doubtful Accounts Receivable	4.3			4.3
Long-term Customer Receivables
Disaggregation of Revenue [Line Items]
Long-term Investments and Receivables, Net	$ 11.3			$ 11.1
Scenario, Forecast | One year or longer
Disaggregation of Revenue [Line Items]
Deferred Revenue			$ 5,000
Deferred Revenue, Percentage of Total, Expected to be Recognized in Next Twelve Months			47.00%
Deferred Revenue, Percentage of Total, Expected to be Recognized Beyond Twelve Months			53.00%

Discontinued Operations - Loss,

Discontinued Operations - Loss, Assets and Liabilities of Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss from discontinued operations, net of income taxes	$ (3.4)	$ (1.3)
Discontinued Operations, Held-for-sale or Disposed of by Sale
Liabilities:
Accounts payable and accrued expenses	54		$ 54
Other noncurrent liabilities	141.3		141
Total liabilities classified as discontinued operations	$ 195.3		$ 195

Discontinued Operations - Patri

Discontinued Operations - Patriot Related Matters (Details) - USD ($) $ in Millions	Jan. 25, 2017	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2007	Oct. 31, 2007
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Estimated fund obligation						$ 40
Amount contributed to the Combined Benefit Fund		$ 0.5	$ 0.6
CombinedBenefitFundLowerEstimate		1
CombinedBenefitFundFutureEstimate		2
Combined Benefit Fund Liability		16		$ 16.4
Combined benefit fund [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax		0.2
Spinoff | Patriot | Black Lung Occupational Disease Liability
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Initially Determined Potential Exposure from Patriot Bankruptcy					$ 150
Potential Exposure from Patriot Bankruptcy		103.1		102.7
Spinoff | UMWA 1974 Pension Plan (UMWA Plan) Litigation | Patriot
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Settlement of claim, amount awarded to other party	$ 75
Litigation settlement, liability		$ 37.8		$ 36.7

Inventories - Schedule of Inven

Inventories - Schedule of Inventory (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Inventories [Line Items]
Materials and supplies	$ 118.9	$ 118.1
Raw coal	50	53.6
Saleable coal	99.6	108.5
Total	268.5	280.2
Reserve for materials and supplies
Inventories [Line Items]
Valuation Allowances and Reserves, Balance	$ 1.1	$ 0.2

Equity Method Investments (Deta

Equity Method Investments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Equity method investments and financing receivables	$ 48.4		$ 45.9
Income (Loss) from Equity Method Investments	3.5	$ 22
Depreciation, depletion and amortization and asset retirement obligation expenses	172.5	169.6
Net interest expense	35.8	36.3
Income tax provision	18.8	10.1
Middlemount Mine
Accounts, Notes, Loans and Financing Receivable [Line Items]
Income (Loss) from Equity Method Investments	$ 3.8	22.2
Equity method investment, ownership percentage	50.00%
Depreciation, depletion and amortization and asset retirement obligation expenses	$ 3.6	3.9
Net interest expense	2.2	3.6
Income tax provision	1.7	5.1
Middlemount Mine | Financing Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, cash received from equity Interest	$ 1.1	$ 35.8

Derivatives and Fair Value Me_4

Derivatives and Fair Value Measurements - Derivatives by Balance Sheet Classification (Details) - Designated as Hedging Instrument - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Asset Derivative
Asset derivatives, gross	$ 169.2	$ 67.5
Effect of counterparty netting, derivative assets	(145.5)	(64.5)
Variation margin posted on derivative assets	(18.2)	0
Net derivative assets and margin as classified in the balance sheets	5.5	3
Liability Derivative
Liability derivatives, gross	(145.6)	(87.5)
Effect of counterparty netting, derivative liabilities	145.5	64.5
Variation margin posted on derivative liabilities	0	21.8
Net derivative liabilities and margin as classified in the balance sheets	(0.1)	(1.2)
Foreign currency option contracts
Asset Derivative
Asset derivatives, gross	1.3	1.2
Liability Derivative
Liability derivatives, gross	0	0
Coal contracts related to forecasted sales
Asset Derivative
Asset derivatives, gross	23	6.6
Liability Derivative
Liability derivatives, gross	(7.9)	(23.1)
Coal trading contracts
Asset Derivative
Asset derivatives, gross	144.9	59.7
Liability Derivative
Liability derivatives, gross	$ (137.7)	$ (64.4)

Derivatives and Fair Value Me_5

Derivatives and Fair Value Measurements - Gains and Losses on Hedging Derivatives (Details) - Designated as Hedging Instrument - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Total (loss) gain recognized in income	$ 48.5	$ 54.6
(Loss) gain realized in income on derivatives	4.8	16
Unrealized (loss) gain recognized in income on derivatives	43.7	38.6
Foreign currency option contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total (loss) gain recognized in income	(1.1)	(4.2)
(Loss) gain realized in income on derivatives	(1.3)	(2.4)
Unrealized (loss) gain recognized in income on derivatives	0.2	(1.8)
Coal contracts related to forecasted sales
Derivative Instruments, Gain (Loss) [Line Items]
Total (loss) gain recognized in income	50.7	59.8
(Loss) gain realized in income on derivatives	10.9	21.2
Unrealized (loss) gain recognized in income on derivatives	39.8	38.6
Coal trading contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total (loss) gain recognized in income	(1.1)	(1)
(Loss) gain realized in income on derivatives	(4.8)	(2.8)
Unrealized (loss) gain recognized in income on derivatives	$ 3.7	$ 1.8

Derivatives and Fair Value Me_6

Derivatives and Fair Value Measurements - Financial Instruments Measured on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	$ 15.4	$ 11.8
Level 1
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Level 2
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	5.4	1.8
Level 3
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	10	10
Foreign currency option contracts
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	1.3	1.2
Foreign currency option contracts | Level 1
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Foreign currency option contracts | Level 2
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	1.3	1.2
Foreign currency option contracts | Level 3
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Coal contracts related to forecasted sales
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	18.8	(21.2)
Coal contracts related to forecasted sales | Level 1
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Coal contracts related to forecasted sales | Level 2
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	18.8	(21.2)
Coal contracts related to forecasted sales | Level 3
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Coal trading contracts
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	(14.7)	21.8
Coal trading contracts | Level 1
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Coal trading contracts | Level 2
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	(14.7)	21.8
Coal trading contracts | Level 3
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Equity securities
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	10	10
Equity securities | Level 1
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Equity securities | Level 2
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Equity securities | Level 3
Derivative [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	$ 10	$ 10

Derivatives and Fair Value Me_7

Derivatives and Fair Value Measurements - Long-term debt (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Current and Long-term debt	$ 1,361.7	$ 1,367
Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Current and Long-term debt	$ 1,406.6	$ 1,366.2

Derivatives and Fair Value Me_8

Derivatives and Fair Value Measurements - Textuals (Details) T in Millions, $ in Millions, $ in Millions	Dec. 31, 2019T	Sep. 30, 2019$ / $	Mar. 31, 2019AUD ($)T	Mar. 31, 2019USD ($)T	Dec. 31, 2018USD ($)
Foreign currency option contracts
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount			$ 975
Coal
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount | T			3.7	3.7
Diesel Fuel Hedge Contracts
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount			$ 0
Scenario, Forecast | Coal
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount | T	2.2
Scenario, Forecast | Minimum | Foreign currency option contracts
Derivatives, Fair Value [Line Items]
Derivative, Exchange Rate Cap | $ / $		0.76
Scenario, Forecast | Maximum | Foreign currency option contracts
Derivatives, Fair Value [Line Items]
Derivative, Exchange Rate Cap | $ / $		0.77
Coal Trading
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net				$ 18.2	$ 21.8
Derivative, Collateral, Right to Reclaim Cash				15.5	16.7
Receivables from Brokers-Dealers and Clearing Organizations				6	2.2
Potential collateralization that may be requested by counterparties due to a material adverse event				$ 0.1	$ 1.3
Coal Trading Positions [Member] | External Credit Rating, Investment Grade [Member] | Coal Trading | Credit Concentration Risk [Member]
Derivatives, Fair Value [Line Items]
Credit Exposure Related to Coal Trading Activities			43.00%	43.00%
Coal Trading Positions [Member] | Non Rated [Member] | Coal Trading | Credit Concentration Risk [Member]
Derivatives, Fair Value [Line Items]
Credit Exposure Related to Coal Trading Activities			57.00%	57.00%

Intangible Contract Assets an_3

Intangible Contract Assets and Liabilities - Balances and Balance Sheet Classifications (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Fresh-Start Adjustment [Line Items]
Assets	$ 60.5	$ 70.9
Liabilities	(79.1)	(90)
Finite-Lived Liabilities, Net	(18.6)	(19.1)
Investments and other assets
Fresh-Start Adjustment [Line Items]
Assets	60.5	70.9
Liabilities	0	0
Finite-Lived Assets, Net	60.5	70.9
Accounts payable and accrued expenses
Fresh-Start Adjustment [Line Items]
Assets	0	0
Liabilities	(14)	(20.3)
Finite-Lived Liabilities, Net	(14)	(20.3)
Other noncurrent liabilities
Fresh-Start Adjustment [Line Items]
Assets	0	0
Liabilities	(65.1)	(69.7)
Finite-Lived Liabilities, Net	(65.1)	(69.7)
Coal supply agreements
Fresh-Start Adjustment [Line Items]
Liabilities	(27.3)	(32.9)
Take-or-pay contracts
Fresh-Start Adjustment [Line Items]
Liabilities	(51.8)	(57.1)
Finite-Lived Liabilities, Net	(51.8)	(57.1)
Coal supply agreements
Fresh-Start Adjustment [Line Items]
Assets	60.5	70.9
Finite-Lived Assets, Net	33.2	38
Take-or-pay contracts
Fresh-Start Adjustment [Line Items]
Assets	$ 0	$ 0

Intangible Contract Assets an_4

Intangible Contract Assets and Liabilities - Textuals (Details) - Fresh Start Reporting - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Sales Contracts
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Presented periods amortization	$ 4.8	$ 29.3
Take-or-pay contracts
Finite-Lived Intangible Liabilities, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Presented periods amortization	$ 5.6	$ 8.3
Scenario, Forecast | Sales Contracts
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Remainder of 2019								$ 22
2020							$ 8
2021						$ 3
2022					$ 1
2023				$ 1
Scenario, Forecast | Take-or-pay contracts
Finite-Lived Intangible Liabilities, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Remainder of 2019								$ 11
2020							$ 9
2021						$ 4
2022					$ 3
2023				$ 3
2024 and thereafter			$ 22

Property, Plant, Equipment an_3

Property, Plant, Equipment and Mine Development (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Land and coal interests	$ 4,149.8	$ 4,148.8
Buildings and improvements	558.3	559.3
Machinery and equipment	1,474	1,456.3
Less: Accumulated depreciation, depletion and amortization	(1,112.6)	(957.4)
Property, plant, equipment and mine development, net	$ 5,069.5	$ 5,207

Leases - Supplemental Income St

Leases - Supplemental Income Statement Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Operating leases
Operating lease cost:
Operating lease cost	$ 15.5
Short-term lease cost	8.3
Variable lease cost	6
Sublease income	(1.4)
Total operating lease cost	28.4
Finance leases
Finance lease cost:
Amortization of right-of-use assets	4.1
Interest on lease liabilities	0.5
Total finance lease cost	$ 4.6

Leases - Supplemental Balance S

Leases - Supplemental Balance Sheeet Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Operating leases:
Operating lease right-of-use assets	$ 97	$ 0
Operating lease liabilities, less current portion	58.2	0
Total operating lease liabilities	88.9
Finance leases:
Accumulated depreciation	(1,112.6)	(957.4)
Property, plant, equipment and mine development, net	5,069.5	5,207
Current portion of long-term debt	34.8	36.5
Long-term debt	1,326.9	1,330.5
Total finance lease liabilities	32.7	$ 40
Operating leases
Operating leases:
Operating lease right-of-use assets	97
Accounts payable and accrued expenses	30.7
Operating lease liabilities, less current portion	58.2
Total operating lease liabilities	$ 88.9
Weighted average remaining lease term
Operating leases	4 years 2 months 12 days
Weighted average discount rate
Operating leases	7.40%
Finance leases
Finance leases:
Property, plant, equipment and mine development	$ 97.8
Accumulated depreciation	(33.4)
Property, plant, equipment and mine development, net	64.4
Current portion of long-term debt	30.8
Long-term debt	1.9
Total finance lease liabilities	$ 32.7
Weighted average remaining lease term
Finance leases	5 years 4 months 24 days
Weighted average discount rate
Finance leases	7.60%

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows for operating leases	$ 24.1
Operating cash flows for finance leases	0.7
Financing cash flows for finance leases	7.3
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	0.5
Finance leases	$ 0

Leases - Maturities of Lease Li

Leases - Maturities of Lease Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Operating Leases
2019	$ 27
2020	28
2021	16.5
2022	11.9
2023	12.2
2024 and thereafter	12.1
Total lease payments	107.7
Less imputed interest	(18.8)
Total lease liabilities	88.9
Finance Leases
2019	28.7
2020	8.1
2021	0.5
2022	0.5
2023	0.5
2024 and thereafter	8.7
Total lease payments	47
Less imputed interest	(14.3)
Finance Lease, Liability	$ 32.7	$ 40

Leases - Textuals (Details)

Leases - Textuals (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Provision for North Goonyella equipment loss	$ 24.7	$ 0		$ 66.4
Operating Leases, Rent Expense				$ 44.7
Leased Equipment
Lessee, Lease, Description [Line Items]
Provision for North Goonyella equipment loss			$ 50.7
Minimum
Lessee, Lease, Description [Line Items]
Operating and Finance Leases Remaining Lease Term	1 year
Maximum
Lessee, Lease, Description [Line Items]
Operating and Finance Leases Remaining Lease Term	23 years

Income Taxes - Textuals (Detail

Income Taxes - Textuals (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Taxes
Income tax provision (benefit)	$ 18.8	$ 10.1
Foreign Tax Authority
Income Taxes
Income tax provision (benefit)	$ (0.1)	$ 0.5

Long-term Debt - Schedule of De

Long-term Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Finance Lease, Liability	$ 32.7	$ 40
Less: Debt issuance costs	(66)	(68.9)
Total debt	1,361.7	1,367
Less: Current portion of long-term debt	34.8	36.5
Long-term debt	1,326.9	1,330.5
Senior Notes | 6.000% Senior Secured Notes due March 2022
Debt Instrument [Line Items]
Long-term debt	$ 500	$ 500
Stated interest rate	6.00%	6.00%
Senior Notes | 6.375% Senior Secured Notes due March 2025
Debt Instrument [Line Items]
Long-term debt	$ 500	$ 500
Stated interest rate	6.375%	6.375%
Term Loan | Senior Secured Term Loan due 2025, net of original issue discount
Debt Instrument [Line Items]
Long-term debt	$ 395	$ 395.9

Long-term Debt - Textuals (Deta

Long-term Debt - Textuals (Details)	1 Months Ended	3 Months Ended		24 Months Ended
	Apr. 30, 2018USD ($)	Mar. 31, 2019USD ($)	Mar. 31, 2018USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Aug. 09, 2018USD ($)	Sep. 18, 2017USD ($)	Apr. 03, 2017USD ($)	Feb. 15, 2017USD ($)
Debt Instrument [Line Items]
Debt issuance cost		$ 66,000,000		$ 66,000,000	$ 68,900,000
Interest expense		35,800,000	$ 36,300,000
Repayments of Long-term Debt, Long-term Capital Lease Obligations, and Capital Securities		$ 8,300,000	8,200,000
Successor Credit Agreement
Debt Instrument [Line Items]
Debt Instrument, Covenant, Fixed Charge Coverage Ratio		2.25
Revolving Credit Facility
Debt Instrument [Line Items]
Interest expense			1,800,000
Revolving Credit Facility | 2017 Revolver
Debt Instrument [Line Items]
Debt issuance cost		$ 4,700,000		4,700,000
Interest expense		1,600,000
Line of Credit Facility, Maximum Borrowing Capacity		350,000,000		$ 350,000,000
Unrestricted Cash Netting Limit		$ 800,000,000
Revolving Credit Facility, Fee on Unused Borrowings		0.50%		0.50%
Aggregate Letters of Credit, Maximum		$ 106,500,000		$ 106,500,000
Revolving Credit Facility | 2017 Revolver | Total Leverage Ration Less Or Equal 2.00 to 1.00
Debt Instrument [Line Items]
Total Leverage Ratio		2		2
Revolving Credit Facility | 2017 Revolver | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate	2.75%	3.25%
London Interbank Offered Rate (LIBOR) Floor	1.00%
Revolving Credit Facility | Letter of Credit
Debt Instrument [Line Items]
Debt Instrument, Base Interest Rate		3.375%		3.375%
Senior Notes | 6.000% Senior Secured Notes due March 2022
Debt Instrument [Line Items]
Stated interest rate		6.00%		6.00%	6.00%
Long-term debt		$ 500,000,000		$ 500,000,000	$ 500,000,000
Debt Instrument, Restricted Payments, Amount Paid						$ 10
Debt Instrument, Restricted Payments, Principal Amount Used to Calculate Payments						1,000
Senior Notes | 6.000% Senior Secured Notes due March 2022 | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Redemption price, percentage		103.00%
Senior Notes | 6.000% Senior Secured Notes due March 2022 | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Redemption price, percentage		101.50%
Senior Notes | 6.375% Senior Secured Notes due March 2025
Debt Instrument [Line Items]
Stated interest rate		6.375%		6.375%	6.375%
Long-term debt		$ 500,000,000		$ 500,000,000	$ 500,000,000
Debt Instrument, Restricted Payments, Amount Paid						30
Debt Instrument, Restricted Payments, Principal Amount Used to Calculate Payments						1,000
Senior Notes | 6.375% Senior Secured Notes due March 2025 | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Redemption price, percentage		104.80%
Senior Notes | 6.375% Senior Secured Notes due March 2025 | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Redemption price, percentage		103.20%
Senior Notes | 6.375% Senior Secured Notes due March 2025 | Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Redemption price, percentage		101.60%
Senior Notes | 6.00% And 6.375% Senior Secured Notes, Successor Notes
Debt Instrument [Line Items]
Debt issuance cost		$ 49,500,000		$ 49,500,000
Interest expense		$ 18,000,000	17,500,000
Senior Notes | 6.00% And 6.375% Senior Secured Notes, Successor Notes | Domestic
Debt Instrument [Line Items]
Collateral, capital stock, percent		100.00%		100.00%
Senior Notes | 6.00% And 6.375% Senior Secured Notes, Successor Notes | Export
Debt Instrument [Line Items]
Collateral, non-voting capital stock, percent		100.00%		100.00%
Collateral, voting capital stock, percent		65.00%		65.00%
Senior Notes | 6.00% And 6.375% Senior Secured Notes, Successor Notes | Peabody Investments (Gibraltar) Limited
Debt Instrument [Line Items]
Collateral, non-voting capital stock, percent		100.00%		100.00%
Collateral, voting capital stock, percent		65.00%		65.00%
Senior Notes | Successor Credit Agreement
Debt Instrument [Line Items]
Debt Instrument, Restricted Payments Basket						650,000,000
Debt Instrument, Restricted Payments Basket, Annual Limit						150,000,000
Other Expenses		$ 1,500,000
Senior Notes | Effect of Plan | 6.000% Senior Secured Notes due March 2022
Debt Instrument [Line Items]
Principal amount									$ 500,000,000
Senior Notes | Effect of Plan | 6.375% Senior Secured Notes due March 2025
Debt Instrument [Line Items]
Principal amount									$ 500,000,000
Term Loan | Successor Credit Agreement
Debt Instrument [Line Items]
Interest expense		5,700,000	$ 6,600,000
Principal amount		400,000,000		$ 400,000,000
Original issue discount and deferred finance costs		$ 37,300,000		$ 37,300,000
Mandatory principal prepayment, percent of excess cash flow		75.00%		75.00%
Mandatory principal prepayment, if required, period payable, threshold		100 days
Excess proceeds from sales of assets, threshold ($10 million or greater)		$ 10,000,000		$ 10,000,000
Repayments of Debt				554,000,000
Restricted payments threshold		$ 450,000,000		450,000,000			$ 50,000,000
Payment for Debt Extinguishment or Debt Prepayment Cost				$ 546,000,000
Debt Instrument, Restricted Payments Basket						$ 19,800,000	$ 450,000,000
Debt Instrument, Covenant, Fixed Charge Coverage Ratio		2
Repayments of Long-term Debt, Long-term Capital Lease Obligations, and Capital Securities	$ 46,000,000
Term Loan | Successor Credit Agreement | Total Leverage Ratio Less or Equal to 2.00 to 1.00 Greater Than 1.50 to 1.00
Debt Instrument [Line Items]
Mandatory principal prepayment, percent of excess cash flow		50.00%		50.00%
Term Loan | Successor Credit Agreement | Total Leverage Ratio Less or Equal to 2.00 to 1.00 Greater Than 1.50 to 1.00 | Maximum
Debt Instrument [Line Items]
Total Leverage Ratio		2		2
Term Loan | Successor Credit Agreement | Total Leverage Ratio Less or Equal to 2.00 to 1.00 Greater Than 1.50 to 1.00 | Minimum
Debt Instrument [Line Items]
Total Leverage Ratio		1.50		1.50
Term Loan | Successor Credit Agreement | Total Leverage Ratio Less or Equal to 1.50 to 1.00 Greater Than 1.00 to 1.00
Debt Instrument [Line Items]
Mandatory principal prepayment, percent of excess cash flow		25.00%		25.00%
Term Loan | Successor Credit Agreement | Total Leverage Ratio Less or Equal to 1.50 to 1.00 Greater Than 1.00 to 1.00 | Maximum
Debt Instrument [Line Items]
Total Leverage Ratio		1.50		1.50
Term Loan | Successor Credit Agreement | Total Leverage Ratio Less or Equal to 1.50 to 1.00 Greater Than 1.00 to 1.00 | Minimum
Debt Instrument [Line Items]
Total Leverage Ratio		1		1
Term Loan | Successor Credit Agreement | Total Leverage Ratio Less or Equal to 1.00 to 1.00
Debt Instrument [Line Items]
Mandatory principal prepayment, percent of excess cash flow		0.00%		0.00%
Total Leverage Ratio		1		1
Term Loan | Successor Credit Agreement | Total Leverage Ration Less Or Equal 2.00 to 1.00
Debt Instrument [Line Items]
Total Leverage Ratio		2		2
Term Loan | Successor Credit Agreement | Total Leverage Ratio Less or Equal 1.25 to 1.00
Debt Instrument [Line Items]
Total Leverage Ratio		1.25		1.25
Dividend payment and stock purchase payment threshold		$ 25,000,000		$ 25,000,000
Term Loan | Successor Credit Agreement | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate		2.75%
Term Loan | Senior Secured Term Loan due 2025, net of original issue discount
Debt Instrument [Line Items]
Long-term debt		$ 395,000,000		395,000,000	$ 395,900,000
Secured Debt		950,000,000		950,000,000
Term Loan | Effect of Plan | Successor Credit Agreement
Debt Instrument [Line Items]
Principal amount								$ 950,000,000
Line of Credit | 2017 Revolver | Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt		$ 350,000,000		$ 350,000,000

Pension and Postretirement Be_3

Pension and Postretirement Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Components of net periodic benefit cost
Net periodic cost (benefit)	$ 4.9	$ 4.5
Defined benefit pension plans
Components of net periodic benefit cost
Service cost for benefits earned	0.5	0.6
Interest cost on projected benefit obligation	8.3	7.8
Expected return on plan assets	(7.8)	(10.7)
Net periodic cost (benefit)	$ 1	(2.3)
Other Defined Benefit Plan Information [Abstract]
Funding threshold	80.00%
Postretirement benefit plans
Components of net periodic benefit cost
Service cost for benefits earned	$ 1.2	2
Interest cost on projected benefit obligation	6.3	7.1
Expected return on plan assets	(0.1)	0
Amortization of prior service cost and net actuarial loss	(2.2)	0
Net periodic cost (benefit)	$ 5.2	$ 9.1

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income - Components of AOCI (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Foreign Currency Translation Adjustment	$ 0.1	$ (0.8)
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), foreign currency translation adjustment, net of tax, beginning of period	(4.5)
Translation Adjustment Functional to Reporting Currency, Gain (Loss), Reclassified to Earnings, Net of Tax	0
Foreign Currency Translation Adjustment	0.1
Accumulated other comprehensive income (loss), foreign currency translation adjustment, net of tax, end of period	(4.4)
Prior Service Credit (Cost) Associated with Postretirement Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income loss prior service cost credit arising during period net of tax, beginning of period	44.6
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, after Tax	(2.2)
Prior service cost for the period	0
Accumulated other comprehensive income loss prior service cost credit arising during period net of tax, end of period	42.4
Total Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Foreign Currency Translation Adjustment	0.1	$ (0.8)
Accumulated other comprehensive income, beginning of period	40.1
Other Comprehensive Income Reclassification Adjustment Net Of Tax	(2.2)
Accumulated other comprehensive income (loss), current period change, net of tax	0.1
Accumulated other comprehensive income, end of period	$ 38

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Income - Reclassification from AOCI (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Prior service credit associated with postretirement plans
Reclassification Adjustment Out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, after Tax	$ (2.2)

Other Events (Details)

Other Events (Details) T in Millions, $ in Millions, $ in Millions	Apr. 30, 2019USD ($)	Jun. 30, 2018USD ($)T	Mar. 31, 2019USD ($)	Mar. 31, 2018AUD ($)	Mar. 31, 2018USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Feb. 06, 2018
Other Commercial Events [Line Items]
Costs Related to North Goonyella Events								$ 58
Insurance Recoveries			$ 125		$ 0
Provision for North Goonyella equipment loss			24.7		0			$ 66.4
Containment and idling costs			36.9
Deductible Amount			50
Insurance Recoveries, Cash Collected			8.1
Proceeds from Sale of Property, Plant, and Equipment			11		23
Net gain on disposals			$ 1.5		30.6
Interest in unincorporated joint venture project			50.00%			50.00%
Stanmore Coal Limited
Other Commercial Events [Line Items]
Coal Reserves, in tons | T		23
Proceeds from Sale of Property, Plant, and Equipment		$ 22	$ 7
Accounts Receivable, Net			7			$ 7
Other
Other Commercial Events [Line Items]
Provision for North Goonyella equipment loss			17.2
Leased Equipment
Other Commercial Events [Line Items]
Provision for North Goonyella equipment loss						$ 50.7
Owned Equipment
Other Commercial Events [Line Items]
Provision for North Goonyella equipment loss			$ 23.2
DTA and PBGC
Other Commercial Events [Line Items]
Equity Method Investment, Ownership Percentage									50.00%
Red Mountain Joint Venture
Other Commercial Events [Line Items]
Proceeds from Sale of Property, Plant, and Equipment					20
Net gain on disposals					7.1
Queensland’s Bowen Basin
Other Commercial Events [Line Items]
Proceeds from Sale of Property, Plant, and Equipment				$ 37
Net gain on disposals					$ 20.6
Scenario, Forecast
Other Commercial Events [Line Items]
Costs Related to North Goonyella Events							$ 275
Scenario, Forecast | Leased Equipment
Other Commercial Events [Line Items]
Costs Related to North Goonyella Events							$ 10
Subsequent Event | Yancoal Technology Development Pty Ltd
Other Commercial Events [Line Items]
Payments to exercise option to acquire equipment	$ 54.2

Earnings per Share (EPS) (Detai

Earnings per Share (EPS) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Jan. 31, 2018
EPS numerator:
Income from continuing operations, net of income taxes	$ 133.3	$ 208.3
Less: Series A Convertible Preferred Stock dividends	0	102.5
Less: Net income (loss) attributable to noncontrolling interests	5.7	(2.1)
Income from continuing operations attributable to common stockholders, before allocation of earnings to participating securities	127.6	107.9
Less: Earnings allocated to participating securities	0	6
Income from continuing operations attributable to common stockholders, after allocation of earnings to participating securities (1)	127.6	101.9
Loss from discontinued operations, net of income taxes	(3.4)	(1.3)
Less: Loss from discontinued operations allocated to participating securities	0	(0.1)
Loss from discontinued operations attributable to common stockholders, after allocation of earnings to participating securities	(3.4)	(1.2)
Net income attributable to common stockholders, after allocation of earnings to participating securities (1)	$ 124.2	$ 100.7
EPS denominator:
Weighted average shares outstanding — basic	108.5	120.9
Impact of dilutive securities	2	2.3
Weighted average shares outstanding — diluted	110.5	123.2
Basic EPS attributable to common stockholders:
Income from continuing operations, per basic share	$ 1.18	$ 0.84
Loss from discontinued operation, per basic share	(0.04)	(0.01)
Basic income per share (in dollars per share)	1.14	0.83
Diluted EPS attributable to common stockholders:
Income from continuing operations, per diluted share	1.15	0.83
Loss from discontinued operations, per diluted share	(0.03)	(0.01)
Diluted income per share (in dollars per share)	$ 1.12	$ 0.82
Earnings Per Share Table Footnotes
Undistributed Earnings (Loss) Allocated to Participating Securities, Diluted	$ 0.1
Weighted Average Number of Shares Outstanding, Diluted		8.4
Earnings per share textuals
Antidilutive shares excluded from EPS calculation	0.3	0.1
Convertible Preferred Stock
Earnings per share textuals
Preferred stock, shares issued	0		0	30
Common Stock | Common Stock
Earnings per share textuals
Common stock, shares converted from convertible preferred stock				59.3

Financial Instruments and Oth_2

Financial Instruments and Other Guarantees - Textuals (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2018
Guarantee Obligations [Line Items]
Surety Bonds outstanding	$ 1,571.3		$ 1,571.3
Letters of credit outstanding, amount	239.6		239.6
Asset retirement obligations	691.8		691.8	$ 686.4
Net interest expense	35.8	$ 36.3
Net impact on collateral requirements	0	214
Provision for North Goonyella equipment loss	24.7	0		$ 66.4
Proceeds from Release of Collateral, Short-term and Long-term		254.1
Secured Debt | Accounts Receivable Securitization Program, April 3, 2020
Guarantee Obligations [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	250		250
Secured Debt | Accounts Receivable Securitization Program, April 1, 2022 [Member]
Guarantee Obligations [Line Items]
Letters of credit outstanding, amount	0		0
Letters of credit drawn on, amount	131.7		131.7
Cash collateral required	0		0
Net interest expense	1.1	$ 1.3
U.S Mining
Guarantee Obligations [Line Items]
Surety Bonds outstanding	1,358.9		1,358.9
Letters of credit outstanding, amount	147.3		147.3
Asset retirement obligations	$ 755.7		755.7
Leased Equipment
Guarantee Obligations [Line Items]
Provision for North Goonyella equipment loss			$ 50.7

Commitments and Contingencies -

Commitments and Contingencies - Commitments (Details) $ in Millions	Mar. 31, 2019USD ($)
Capital Addition Purchase Commitments
Long-term Purchase Commitment [Line Items]
Unrecorded Unconditional Purchase Obligation	$ 134.6

Commitments and Contingencies_2

Commitments and Contingencies - Contingencies (Details) - 3 months ended Mar. 31, 2019 $ in Millions, $ in Billions	AUD ($)	USD ($)
Maximum | Monto Coal Pty Limited
Loss Contingency [Abstract]
Damages sought, value	$ 1.1
Berenergy Corporation vs. the Company | Berenergy
Loss Contingency [Abstract]
Loss contingency accrual		$ 13.1
Reasonable Value of Oil Reserves		$ 1

Segment Information Segment Res

Segment Information Segment Results (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Reportable segment results
Revenues	$ 1,250.6	$ 1,462.7
Total Adjusted EBITDA	253.9	363.9
Net gain on disposals	1.5	30.6
Iffley Land Transaction
Reportable segment results
Net gain on disposals		20.6
Red Mountain Joint Venture
Reportable segment results
Net gain on disposals		7.1
Seaborne Thermal Mining | Operating Segments
Reportable segment results
Revenues	251	201.4
Total Adjusted EBITDA	94.7	61.6
Seaborne Metallurgical Mining | Operating Segments
Reportable segment results
Revenues	324.5	466.2
Total Adjusted EBITDA	85.8	166.4
Powder River Basin Mining | Operating Segments
Reportable segment results
Revenues	287.3	389.3
Total Adjusted EBITDA	36.4	74.5
Midwestern U.S. Mining | Operating Segments
Reportable segment results
Revenues	179.1	201.7
Total Adjusted EBITDA	33.3	31.2
Western U.S. Mining | Operating Segments
Reportable segment results
Revenues	155.7	143.7
Total Adjusted EBITDA	42.6	32
Corporate and Other | Corporate, Non-Segment
Reportable segment results
Revenues	53	60.4
Total Adjusted EBITDA	$ (38.9)	$ (1.8)

Segment Information Reconciliat

Segment Information Reconciliation to Adjusted EBITDA (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Segment Reporting [Abstract]
Income from continuing operations, net of income taxes	$ 133.3	$ 208.3
Depreciation, depletion and amortization	172.5	169.6
Asset retirement obligation expenses	13.8	12.3
Provision for North Goonyella equipment loss	24.7	0	$ 66.4
North Goonyella insurance recoveries - equipment (1)	(91.1)	0
Changes in deferred tax asset valuation allowance and reserves and amortization of basis difference related to equity affiliates	0	(7.6)
Interest expense	35.8	36.3
Interest income	(8.3)	(7.2)
Reorganization items, net	0	(12.8)
Unrealized gains on economic hedges	(39.8)	(38.6)
Unrealized (gains) losses on non-coal trading derivative contracts	(0.2)	1.8
Fresh start take-or-pay contract-based intangible recognition	(5.6)	(8.3)
Income tax provision	18.8	10.1
Total Adjusted EBITDA	253.9	363.9
Insurance Recoveries	125	$ 0
Business Interruption Losses	$ 33.9