Payments to Acquire Productive Assets and Capital Expenditures Incurred But Not Yet Paid

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- Definition

Future cash outflow to pay for purchases of fixed assets that have occurred.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (c)

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- Definition

Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: 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

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- Definition

The cumulative amount of depreciation (related to capitalized assets classified as property, plant and equipment not otherwise defined in the taxonomy) that has been recognized in the income statement.

+ References

No definition available.

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- Definition

The net amount of capitalized assets classified as property, plant and equipment not otherwise defined in the taxonomy.

+ References

No definition available.

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Property, Plant and Equipment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	$ 340,992us-gaap_PropertyPlantAndEquipmentOther		$ 337,832us-gaap_PropertyPlantAndEquipmentOther
Accumulated depreciation	(225,035)		(218,951)
Total property, plant, and equipment, net	115,957		118,881
Payments to Acquire Productive Assets [Abstract]
Total capital expenditures	28,375	24,674
Non-cash and accruals	(473)	1,459
Cash capital spend for the period	27,902	26,133
Stillwater Mine [Member]
Payments to Acquire Productive Assets [Abstract]
Total capital expenditures	21,013	17,746
East Boulder Mine [Member]
Payments to Acquire Productive Assets [Abstract]
Total capital expenditures	4,269	4,439
Other Mine [Member]
Payments to Acquire Productive Assets [Abstract]
Total capital expenditures	3,093	2,489
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	153,795		152,421
Buildings and structural components [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	170,365		169,609
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	9,488		9,488
Construction-in progress [Member] \| Stillwater Mine [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	2,145		2,633
Construction-in progress [Member] \| East Boulder Mine [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	1,458		1,539
Construction-in progress [Member] \| Marathon Property [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	148		148
Construction-in progress [Member] \| Processing Facilities and Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	$ 3,593		$ 1,994