XML 174 R150.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Summary Quarterly Financial Information Textuals (Details) - USD ($) $ in Millions |  |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | ---
Nov. 28, 2017 | Nov. 27, 2017 | Apr. 01, 2017 | Jul. 31, 2018 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Apr. 01, 2017 | Mar. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2016
Successor |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Quarterly Financial Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Disposition of Assets |  |  |  |  |  | $ 20.7 |  | $ 30.6 | $ 83.1 |  |  |  |  | $ 84.0 | $ 48.2 |
Restructuring Costs and Asset Impairment Charges |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.0 | 0.0 |
Provision for North Goonyella equipment loss |  |  |  |  | $ 17.1 | 49.3 |  |  |  |  |  |  |  | 0.0 | 66.4 |
Payments of Debt Restructuring Costs |  |  |  |  |  |  |  |  | 6.6 |  |  |  |  |  |  |
Income (Loss) from Equity Method Investments |  |  |  |  |  | 17.2 | $ 25.2 | 22.0 | 22.8 | $ 10.5 | $ 15.7 |  |  | 49.0 | 68.1 |
Acquisition costs related to Shoal Creek Mine |  |  |  |  |  | 4.9 |  |  |  |  |  |  |  | 0.0 | 7.4 |
Reorganization items, net |  |  |  |  |  |  |  | 12.8 |  |  |  |  |  | 0.0 | (12.8) |
Interest expense |  |  |  |  | 36.5 | 38.2 | 38.3 | 36.3 |  | 42.5 | $ 41.4 |  |  | 119.7 | 149.3 |
Investment Income, Interest |  |  |  |  | 9.3 | 10.1 | $ 7.0 | 7.2 |  |  |  |  |  | 5.6 | 33.6 |
Loss on early debt extinguishment |  |  |  |  |  |  |  |  | 8.0 | $ 12.9 |  |  |  | (20.9) | (2.0) |
Net mark-to-market adjustment on actuarially determined liabilities |  |  |  |  | $ 125.5 |  |  |  | 45.2 |  |  |  |  | (45.2) | (125.5) |
Successor | Burton Mine |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Quarterly Financial Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Disposition of Assets |  | $ 52.2 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  | 52.2 |  |  |  |  | 52.2 | 0.0 |
Successor | Springfield Reclamation Liability |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Quarterly Financial Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Disposition of Assets | $ 31.2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  | $ 31.2 |  |  |  |  | $ 31.2 | $ 0.0 |
Successor | Iffley Land Transaction |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Quarterly Financial Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Disposition of Assets |  |  |  |  |  |  |  | $ 20.6 |  |  |  |  |  |  |  |
Successor | Stanmore Coal Limited |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Quarterly Financial Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Disposition of Assets |  |  |  | $ 20.5 |  | $ 20.5 |  |  |  |  |  |  |  |  |  |
Predecessor |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Quarterly Financial Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Disposition of Assets |  |  |  |  |  |  |  |  |  |  |  | $ 22.8 |  |  |  | $ 23.2
Restructuring Costs and Asset Impairment Charges |  |  |  |  |  |  |  |  |  |  |  | 30.5 | $ 30.5 |  |  | 247.9
Provision for North Goonyella equipment loss |  |  |  |  |  |  |  |  |  |  |  | 0.0 |  |  |  | 0.0
Income (Loss) from Equity Method Investments |  |  |  |  |  |  |  |  |  |  |  | 15.0 | 15.0 |  |  | 16.2
Acquisition costs related to Shoal Creek Mine |  |  |  |  |  |  |  |  |  |  |  | 0.0 |  |  |  | 0.0
Reorganization items, net |  |  | $ 585.8 |  |  |  |  |  |  |  |  | 627.2 | $ 41.4 |  |  | 159.0
Interest expense |  |  |  |  |  |  |  |  |  |  |  | 32.9 |  |  |  | 298.6
Investment Income, Interest |  |  |  |  |  |  |  |  |  |  |  | 2.7 |  |  |  | 5.7
Loss on early debt extinguishment |  |  |  |  |  |  |  |  |  |  |  | 0.0 |  |  |  | (29.5)
Net mark-to-market adjustment on actuarially determined liabilities |  |  |  |  |  |  |  |  |  |  |  | 0.0 |  |  |  | 0.0
Predecessor | Burton Mine |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Quarterly Financial Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  |  |  | 0.0 |  |  |  | 0.0
Predecessor | Springfield Reclamation Liability |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Quarterly Financial Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  |  |  | $ 0.0 |  |  |  | $ 0.0

X
- Definition Mark-to-Market Adjustment on Pension and Postretirement Plans, Net + References No definition available. + Details
Name: | btu_MarktoMarketAdjustmentonPensionandPostretirementPlansNet
Namespace Prefix: | btu_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Provision for equipment loss + References No definition available. + Details
Name: | btu_Provisionforequipmentloss
Namespace Prefix: | btu_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition [Line Items] for Quarterly Financial Information [Table] + References No definition available. + Details
Name: | btu_QuarterlyFinancialInformationLineItems
Namespace Prefix: | btu_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460 + Details
Name: | us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2443-110228 + Details
Name: | us-gaap_GainLossOnDispositionOfAssets1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
Name: | us-gaap_GainLossOnSaleOfProperties
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629 + Details
Name: | us-gaap_GainsLossesOnExtinguishmentOfDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(12)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(10)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)(f)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
Name: | us-gaap_IncomeLossFromEquityMethodInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of the cost of borrowed funds accounted for as interest expense. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.9) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
Name: | us-gaap_InterestExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(b)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
Name: | us-gaap_InvestmentIncomeInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cash outflow for cost incurred in the modification of term of existing debt agreement in order for the entity to achieve some advantage. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
Name: | us-gaap_PaymentsOfDebtRestructuringCosts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Total amount of reorganization items. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 852 -SubTopic 10 -Section 55 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56145-112766 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 852 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=64805424&loc=d3e55730-112764 + Details
Name: | us-gaap_ReorganizationItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
Name: | us-gaap_RestructuringCostsAndAssetImpairmentCharges
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_StatementScenarioAxis=us-gaap_SuccessorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=btu_BurtonMineMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=btu_SpringfieldReclamationLiabilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CounterpartyNameAxis=btu_IffleyLandTransactionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CounterpartyNameAxis=btu_StanmoreCoalLimitedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementScenarioAxis=us-gaap_PredecessorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |