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Asset Impairment Review (Narrative) (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2016 USD ($)
Impairment Effects on Earnings Per Share [Line Items] |
Asset impairment charge | $ 16,560
Property, Plant and Equipment [Member] |
Impairment Effects on Earnings Per Share [Line Items] |
Asset impairment charge | 15,100
Carlisle Assets [Member] |
Impairment Effects on Earnings Per Share [Line Items] |
Mine carring value | 118,000
Asset impairment charge | $ 1,500

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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=51824106&loc=d3e2420-110228 Reference 2: 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 + Details
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- Definition Mineral properties, net of adjustments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -Section 25 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=56951519&loc=d3e64895-109465 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details
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