Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Current assets
Cash and cash equivalents	$ 298.0	$ 444.0
Accounts receivable, net of allowance for doubtful accounts of $5.8 at December 31, 2014 and $7.4 at December 31, 2013	563.1us-gaap_AccountsReceivableNetCurrent	557.9us-gaap_AccountsReceivableNetCurrent
Inventories	406.5us-gaap_InventoryNet	506.7us-gaap_InventoryNet
Assets from coal trading activities, net	57.6btu_AssetsFromCoalTradingActivitiesNet	36.1btu_AssetsFromCoalTradingActivitiesNet
Deferred income taxes	80.0us-gaap_DeferredTaxAssetsNetCurrent	66.4us-gaap_DeferredTaxAssetsNetCurrent
Other current assets	305.8us-gaap_OtherAssetsCurrent	381.6us-gaap_OtherAssetsCurrent
Total current assets	1,711.0us-gaap_AssetsCurrent	1,992.7us-gaap_AssetsCurrent
Property, plant, equipment and mine development, net	10,577.3us-gaap_PropertyPlantAndEquipmentNet	11,082.5us-gaap_PropertyPlantAndEquipmentNet
Deferred income taxes	0.7us-gaap_DeferredTaxAssetsNetNoncurrent	7.8us-gaap_DeferredTaxAssetsNetNoncurrent
Investments and other assets	902.1us-gaap_OtherAssetsNoncurrent	1,050.4us-gaap_OtherAssetsNoncurrent
Total assets	13,191.1us-gaap_Assets	14,133.4us-gaap_Assets
Current liabilities
Current maturities of long-term debt	21.2	31.7
Liabilities from coal trading activities, net	32.7	6.1
Accounts payable and accrued expenses	1,809.2	1,764.0
Total current liabilities	1,863.1us-gaap_LiabilitiesCurrent	1,801.8us-gaap_LiabilitiesCurrent
Long-term debt, less current maturities	5,965.6	5,970.7
Deferred income taxes	89.1	40.9
Asset retirement obligations	722.3	691.8
Accrued postretirement benefit costs	781.9	684.0
Other noncurrent liabilities	1,042.6us-gaap_OtherLiabilitiesNoncurrent	996.3us-gaap_OtherLiabilitiesNoncurrent
Total liabilities	10,464.6us-gaap_Liabilities	10,185.5us-gaap_Liabilities
Stockholders' equity
Additional paid-in capital	2,383.3	2,340.0
Treasury shares, at cost - 14.0 shares as of December 31, 2014 and 13.8 shares as of December 31, 2013	(467.1)us-gaap_TreasuryStockValue	(464.7)us-gaap_TreasuryStockValue
Retained earnings	1,570.5	2,449.8
Accumulated other comprehensive loss	(764.8)	(419.2)
Peabody Energy Corporation's stockholders' equity	2,724.8us-gaap_StockholdersEquity	3,908.7us-gaap_StockholdersEquity
Noncontrolling interests	1.7us-gaap_MinorityInterest	39.2us-gaap_MinorityInterest
Total stockholders' equity	2,726.5	3,947.9
Total liabilities and stockholders' equity	13,191.1	14,133.4
Preferred Stock [Member]
Stockholders' equity
Preferred Stock	0	0
Perpetual Preferred Stock [Member]
Stockholders' equity
Preferred Stock	0	0
Series Common Stock [Member]
Stockholders' equity
Common Stock	0	0
Common Stock [Member]
Stockholders' equity
Common Stock	$ 2.9	$ 2.8

Assets From Coal Trading Activities Net.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 4.E)

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section E

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29-31)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30, 31

-Article 5

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4568447-111683

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-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

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-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 55

-Paragraph 4I

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- Definition

The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23315-112656

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