depreciation, depletion and amortization production and nonproduction

No definition available.

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- Definition

Measure of Segment Profit or Loss used by Chief Operating Decision Maker to make decisions and allocate resources

+ References

No definition available.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.18)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 7

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 18

-Article 5

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- Definition

Revenue derived from sale of coal and related products. Also includes rendering of services and selling of products for exploration, development, mining, and processing, as well as supporting activities.

+ 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 210.5-03.1(a),(d))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

The other noncash expense, not otherwise specified in the taxonomy, charged against earnings in the period to allocate the cost of tangible and intangible assets over their remaining economic lives.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.3)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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Segment Information (Schedule of Operating Segment Results) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Revenues	$ 745,192us-gaap_CoalProductsAndServicesRevenue	$ 742,180us-gaap_CoalProductsAndServicesRevenue	$ 713,776us-gaap_CoalProductsAndServicesRevenue	$ 735,971us-gaap_CoalProductsAndServicesRevenue	$ 719,386us-gaap_CoalProductsAndServicesRevenue	$ 791,269us-gaap_CoalProductsAndServicesRevenue	$ 766,332us-gaap_CoalProductsAndServicesRevenue	$ 737,370us-gaap_CoalProductsAndServicesRevenue	$ 2,937,119us-gaap_CoalProductsAndServicesRevenue	$ 3,014,357us-gaap_CoalProductsAndServicesRevenue	$ 3,768,126us-gaap_CoalProductsAndServicesRevenue
Adjusted EBITDA									280,143aci_MeasureofSegmentProfitorLoss	252,146aci_MeasureofSegmentProfitorLoss	579,872aci_MeasureofSegmentProfitorLoss
Depreciation, depletion and amortization									418,748	426,442	492,211
Amortization of acquired sales contracts, net									(13,187)	(9,457)	(25,189)
Total assets	8,429,723us-gaap_Assets				8,990,193us-gaap_Assets				8,429,723us-gaap_Assets	8,990,193us-gaap_Assets	10,006,777us-gaap_Assets
Capital expenditures									147,286	296,984	395,225
PRB [Member]
Segment Reporting Information [Line Items]
Revenues									1,490,377	1,482,812	1,524,536
Adjusted EBITDA									198,074	206,910	262,155
Depreciation, depletion and amortization									168,522	171,324	166,539
Amortization of acquired sales contracts, net									(3,961)	(3,656)	(1,987)
Total assets	1,772,230				1,841,835				1,772,230	1,841,835	1,972,522
Capital expenditures									44,305	9,784	23,410
APP [Member]
Segment Reporting Information [Line Items]
Revenues									1,108,358	1,145,801	1,793,576
Adjusted EBITDA									110,693	88,883	405,981
Depreciation, depletion and amortization									205,732	202,952	271,221
Amortization of acquired sales contracts, net									(9,433)	(10,364)	(23,926)
Total assets	3,379,834				3,971,764				3,379,834	3,971,764	3,875,105
Capital expenditures									23,638	167,759	275,476
Other Segments [Member]
Segment Reporting Information [Line Items]
Revenues									338,384	385,744	450,014
Adjusted EBITDA									56,612	94,948	112,982
Depreciation, depletion and amortization									40,125	45,741	49,911
Amortization of acquired sales contracts, net									207	4,563	724
Total assets	339,809				402,922				339,809	402,922	834,287
Capital expenditures									12,993	23,122	68,220
Corporate, Other and Eliminations [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA									(85,236)	(138,595)	(201,246)
Depreciation, depletion and amortization									4,369	6,425	4,540
Amortization of acquired sales contracts, net									0	0
Total assets	2,937,850				2,773,672				2,937,850	2,773,672	3,324,863
Capital expenditures									$ 66,350	$ 96,319	$ 28,119