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.

+ Details

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- Definition

Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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Period Type:	duration

- 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 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Section 40

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-SubTopic 50

-Section 40

-Paragraph 4

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ 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)

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-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

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- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

+ References

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

-Publisher FASB

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-Topic 940

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-Section 25

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 5

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- Definition

The net amount of nonoperating interest income (expense).

+ References

No definition available.

+ Details

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- Definition

The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

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-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7)

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

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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

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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-Paragraph 2

-Subparagraph (SX 210.5-03.3)

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- Definition

The aggregate amount provided for estimated restructuring charges, remediation costs, and asset impairment loss during an accounting period. Generally, these items are either unusual or infrequent, but not both (in which case they would be extraordinary items).

+ References

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Segment Information (Reconciliation of Segment Income from Operations to Consolidated Income Before Income Taxes) (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 [Abstract]
Adjusted EBITDA									$ 280,143aci_MeasureofSegmentProfitorLoss	$ 252,146aci_MeasureofSegmentProfitorLoss	$ 579,872aci_MeasureofSegmentProfitorLoss
Depreciation, depletion and amortization									(418,748)	(426,442)	(492,211)
Other Depreciation and Amortization									13,187	9,457	25,189
Asset impairment and mine closure costs	(17,541)	(5,060)	(1,512)	0	0	(200,397)	(20,482)	0	(24,113)	(220,879)	(539,182)
Goodwill impairment						0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss	(265,423)us-gaap_GoodwillImpairmentLoss	(330,680)us-gaap_GoodwillImpairmentLoss
Gain (Loss) Related to Litigation Settlement									0	(12,000)	0
Interest expense, net									(383,188)	(374,664)	(312,142)
Net loss resulting from early retirement and refinancing of debt									0	(42,921)	(23,668)
Nonoperating expense										(42,921)us-gaap_NonoperatingIncomeExpense	(23,668)us-gaap_NonoperatingIncomeExpense
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest									$ (532,719)	$ (1,080,726)	$ (1,092,822)