Additional interest income under a full accrual basis

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- Definition

Adjustment to Discounted Value of Note Receivable

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No definition available.

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- Definition

Business Acquisition, Percentage of Undivided Interests Acquired

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No definition available.

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- Definition

Percentage of Agreed Sale Price as Final Installment Payment

+ References

No definition available.

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- Definition

Sale of Business, Percentage of Ownership Before Transaction

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No definition available.

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- Definition

For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.9)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.5)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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- 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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

Reference 2: 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=26872669&loc=d3e20235-122688

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- Definition

Aggregate carrying amount, as of the balance sheet date, of investments and other noncurrent assets not separately disclosed in the balance sheet due to materiality considerations. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

+ References

No definition available.

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ 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 210.5-02.3)

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Article 5

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Financing Receivables (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income	$ 15.4us-gaap_InvestmentIncomeInterest	$ 15.7us-gaap_InvestmentIncomeInterest	$ 24.5us-gaap_InvestmentIncomeInterest
Middlemount Mine [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Equity method investment, ownership percentage	50.00%
Basis spread over Australian Bank Bill Swap Reference Rate	3.50%
Interest income	4.8	6.4
Additional interest income under a full accrual basis	6.4	5.8
Codrilla Mine Project [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of ownership before selldown				85.00%
Percentage of agreed sale price as final installment payment due	40.00%
Adjustment to discounted value of note receivable		1.6
Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net	0	0.1
Investments and other assets	347.2	351.7
Total financing receivables	347.2	351.8
Financing Receivable [Member] \| Middlemount Mine [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Investments and other assets	319.6	323.2
Financing Receivable [Member] \| Codrilla Mine Project [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Investments and other assets	$ 27.6	$ 28.5
Middlemount Mine [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Equity method investment, ownership percentage	50.00%	50.00%
Coppabella, Moorvale, and Codrilla Mines [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of undivided interests acquired				73.30%