Bankruptcy Claims, Amount of Tax Refunds to be Foregone to Settle Claims

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- Definition

Bankruptcy Claims, Amount to be Paid to Settle Claims

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Bankruptcy Claims, Amount to be Transferred to Settle Claims

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- Definition

Environmental Claims Number of PRP National Priority List Sites Involved

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Ownership Percentage In subsidiaries.

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
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-Section 50
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Amount of bankruptcy claim filed with bankruptcy court.

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Amount of loss contingency liability.

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Amount of damages awarded to the plaintiff in the legal matter.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Number of defendants named in a legal action.

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Commitments and Contingencies - Contingencies (Details) AUD in Millions, $ in Millions					6 Months Ended
	Nov. 17, 2016 USD ($)	Oct. 13, 2016 USD ($)	Oct. 11, 2016 USD ($)	Aug. 19, 2016 USD ($)	Jun. 30, 2017 AUD defendant site	Jun. 30, 2017 USD ($)	Mar. 16, 2017 USD ($)	Dec. 31, 2016 USD ($)
Monto Coal Pty Limited
Loss Contingency [Abstract]
Ownership percentage in subsidiaries						51.00%
Number of defendants \| defendant					3
Gold Fields
Loss Contingency [Abstract]
Number of national priority list sites based on the Superfund Amendments and Reauthorization Act of 1986 at which Gold Fields or the former affiliate, has been named a potentially responsible party (PRP) \| site					4
Undiscounted environmental clean-up liabilities, total								$ 62.8
Minimum \| Monto Coal Pty Limited
Loss Contingency [Abstract]
Damages sought, value \| AUD					AUD 15.6
Maximum \| Monto Coal Pty Limited
Loss Contingency [Abstract]
Damages sought, value \| AUD					AUD 1,800.0
Berenergy Corporation vs. the Company \| Berenergy
Loss Contingency [Abstract]
Litigation settlement damages awarded to plaintiff		$ 0.9
Loss contingency accrual						$ 13.1
Bankruptcy unliquidated, general unsecured claim \| Blue Tee
Loss Contingency [Abstract]
Bankruptcy claims, amount of claims filed				$ 65.6
Bankruptcy additional unliquidated, in an unknown amount \| Blue Tee
Loss Contingency [Abstract]
Bankruptcy claims, amount of claims filed				150.0
Bankruptcy further contingent claims, at known and unknown sites \| Blue Tee
Loss Contingency [Abstract]
Bankruptcy claims, amount of claims filed				$ 500.0
Bankruptcy unliquidated, secured and general unsecured \| Gold Fields
Loss Contingency [Abstract]
Bankruptcy claims, amount of claims filed	$ 1,200.0		$ 2,700.0
Debtors vs. Blue Tee
Loss Contingency [Abstract]
Bankruptcy claims, amount of federal tax refunds to be foregone to settle claims							$ 11.0
Bankruptcy claims, amount of insurance settlement proceeds to be transferred to settle claims							12.0
Bankruptcy claims, amount to be paid directly to settle claims							$ 20.0