Cash Collateral Required

No definition available.

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

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-Publisher FASB
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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

Amount of the cost of borrowed funds accounted for as interest expense.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

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.

+ References

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Financial Instruments and Other Guarantees (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2017	Apr. 01, 2017	Jun. 30, 2016	Jun. 30, 2016	Apr. 03, 2017	Dec. 31, 2016
Obligations [Member]
Guarantee Obligations [Line Items]
Restricted cash	$ 561.7					$ 529.3
U.S Mining
Guarantee Obligations [Line Items]
Asset retirement obligations	378.6
Australian Mining
Guarantee Obligations [Line Items]
Asset retirement obligations	256.5
Reclamation Bonding Surety Bond \| U.S Mining \| Surety Bond
Guarantee Obligations [Line Items]
Long-term debt	1,147.6
Secured Debt \| Accounts Receivable Securitization Program, April 3, 2020
Guarantee Obligations [Line Items]
Long-term debt	0.0
Maximum borrowing capacity					$ 250.0
Letters of credit outstanding, amount	171.5
Cash collateral required	0.0
Interest expense	$ 3.9	$ 2.0	$ 2.4	$ 3.2
Secured Debt \| Former Securitization Facility
Guarantee Obligations [Line Items]
Cash collateral required						40.5
Obligations [Member]
Guarantee Obligations [Line Items]
Restricted cash						$ 13.8