Business acquisition cost of acquired entity cash purchase price per share.

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- Definition

Business Acquisition, Cost Of Acquired Entity, Cash Purchase Price Per Share If Company Meets Ownership Percentage Threshold

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- Definition

Business acquisition percentage of voting interests acquired by other company.

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- Definition

Business Acquisitions, Days to Complete Financing

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- Definition

Business combination merged company voting interest in acquiree company.

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- Definition

Company's Future Ownership Percent in PEAMCoal

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- Definition

Debt Instrument, Base Interest Rate

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- Definition

Debt Instrument, Libor Interest Rate

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- Definition

Debt Instrument, Quarterly Amortization Percentage

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- Definition

Debt Instrument, Rate Margin Over Federal Funds Rate

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Debt Instrument, Rate Spread Over Libor

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- Definition

Funds Remaining with MF Global

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- Definition

Line of Credit Facility, Duration Fee on 180th Day

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- Definition

Line of Credit Facility, Duration Fee on 270th Day

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- Definition

Line of Credit Facility, Duration Fee on 90th Day

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- Definition

Line Of Credit Facility, Maturity Period

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- Definition

Peam Coal Ownership Percent, Making the Takeover Offer Unconditional

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- Definition

The acquisition-date fair value of the equity interests of the acquirer, including the number of instruments or interests issued or issuable in consideration for the business combination.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph f(4)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 88-16

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-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Percentage of voting equity interests acquired in the business combination.

+ References

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- Definition

Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

-Paragraph 8

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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- Definition

Amount borrowed under the credit facility as of the balance sheet date.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Regulation S-X (SX)

-Number 210

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

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-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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- Definition

The cash outflow associated with the acquisition of a controlling interest in another entity or an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, joint venture or equity method investment).

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 15, 17

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-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 (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3213-108585

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Subsequent Events (Details)	3 Months Ended	9 Months Ended										3 Months Ended	9 Months Ended
Subsequent Events (Details)	Sep. 30, 2011 USD ($)	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Oct. 25, 2011 days	Oct. 23, 2011	Nov. 02, 2011 Acquisition [Member] USD ($)	Nov. 02, 2011 Acquisition [Member] AUD	Sep. 30, 2011 Acquisition [Member] AUD	Aug. 01, 2011 Acquisition [Member] AUD	Sep. 30, 2011 Maximum [Member] Financing [Member] Bridge Loan [Member]	Oct. 28, 2011 Maximum [Member] Financing [Member] Term Loan [Member]	Sep. 30, 2011 Financing [Member] Bridge Loan [Member] USD ($)	Sep. 30, 2011 Financing [Member] Bridge Loan [Member] USD ($)	Nov. 03, 2011 Financing [Member] Bridge Loan [Member] USD ($)	Oct. 28, 2011 Financing [Member] Bridge Loan [Member] USD ($)	Jul. 29, 2011 Financing [Member] Bridge Loan [Member] USD ($)	Sep. 30, 2011 Financing [Member] Bridge Loan [Member] Minimum [Member]	Nov. 03, 2011 Financing [Member] Term Loan [Member] USD ($)	Oct. 28, 2011 Financing [Member] Term Loan [Member] USD ($)	Oct. 28, 2011 Financing [Member] Term Loan [Member] Minimum [Member]	Oct. 31, 2011 Bankruptcy of Coal Trading Broker [Member] USD ($)	Sep. 30, 2011 Bridge Loan [Member] USD ($)
Subsequent Event [Line Items]
Ownership percentage of the Company in the newly formed company	100.00%	100.00%							60.00%
Ownership percentage of the joint owner in the newly formed company									40.00%
PEAMCoal Ownership Percent, Making the Takeover Offer Unconditional					50.01%
Business Acquisitions, Days to Complete Financing				90
Cash price per share for proposed acquisition									16.00
Business Acquisition, Cost Of Acquired Entity, Cash Purchase Price Per Share If Company Meets Ownership Percentage Threshold								16.25
Business Acquisition, Ownership Percentage Threshold	90.00%	90.00%
Implied value for the equity of proposed acquired company						$ 5,100,000,000	4,900,000,000
Payments to Acquire Businesses and Interest in Affiliates	45,500,000	45,500,000	0
Relevant interest percentage in proposed acquisition by newly formed company						75.50%	75.50%
Financing Facility, Maximum Borrowing Capacity																2,000,000,000			1,000,000,000
Bridge Loan, Maturity Period													364 days
Bridge Loan, Commitment Fees and Debt Issuance Costs												12,700,000	12,700,000
Bridge Loan, Current Borrowing Capacity															1,000,000,000
Financing Facility, Rate Margin Over Federal Funds Rate												0.50%	0.50%						0.50%
Financing Facility, Rate Spread Over Libor												1.00%	1.00%						1.00%
Financing Facility, Libor Interest Rate										4.00%	3.00%						3.00%			1.75%
Financing Facility, Base Interest Rate										3.00%	2.00%						2.00%			0.75%
Bridge Loan, Duration Fee on 90th Day												1.00%	1.00%
Bridge Loan, Duration Fee on 180th Day												1.50%	1.50%
Bridge Loan, Duration Fee on 270th Day												2.00%	2.00%
Term Loan, Quarterly Amortization Percentage																			1.25%
Financing Facility, Amount Outstanding														0				1,000,000,000				0
Funds remaining with MF Global																					$ 39,000,000