Adjustment to Discounted Value of Note Receivable

No definition available.

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- Definition

Business Acquisition, Percentage of Undivided Interests Acquired

+ References

No definition available.

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- Definition

Percentage of Agreed Sale Price as Final Installment Payment

+ References

No definition available.

+ Details

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- Definition

Sale of Business, Percentage of Ownership Before Transaction

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

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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 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

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- Definition

Aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet. Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer).

+ 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 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

+ 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)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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Financing Receivables (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
Financing Receivables (Details) - USD ($) $ in Millions	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2011
Financing Receivables [Line Items]
Other current assets	$ 503.1		$ 305.8	$ 503.1	$ 305.8
Interest income				7.7	15.4	$ 15.7
Asset Impairment	$ 377.0	$ 900.8	154.4	$ 1,277.8	154.4	528.3
Middlemount Mine [Member]
Financing Receivables [Line Items]
Equity method investment, ownership percentage	50.00%			50.00%
Basis spread over Australian Bank Bill Swap Reference Rate				3.50%
Codrilla Mine Project [Member]
Financing Receivables [Line Items]
Percentage of ownership before selldown							85.00%
Percentage of agreed sale price as final installment payment due	40.00%			40.00%
Adjustment to discounted value of note receivable						$ 1.6
Financing Receivable [Member]
Financing Receivables [Line Items]
Other current assets	$ 20.0		0.0	$ 20.0	0.0
Investments and other assets	65.2		347.2	65.2	347.2
Total financing receivables	85.2		347.2	85.2	347.2
Financing Receivable [Member] \| Middlemount Mine [Member]
Financing Receivables [Line Items]
Investments and other assets	65.2		319.6	65.2	319.6
Financing Receivable [Member] \| Codrilla Mine Project [Member]
Financing Receivables [Line Items]
Other current assets	$ 20.0			$ 20.0
Investments and other assets			$ 27.6		$ 27.6
Middlemount Mine [Member]
Financing Receivables [Line Items]
Equity method investment, ownership percentage	50.00%		50.00%	50.00%	50.00%
Coppabella, Moorvale, and Codrilla Mines [Member]
Financing Receivables [Line Items]
Percentage of undivided interests acquired							73.30%