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- Definition

Payments to Acquire Productive Assets and Capital Lease Obligations Incurred

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- Definition

The increase (decrease) during the reporting period of obligations, not classified as trade payables, incurred and payable for the acquisition of merchandise, materials, supplies, and services pertaining to construction projects.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

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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.

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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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Amount of accumulated depreciation of long-lived, physical assets used to produce goods and services and not intended for resale, classified as other.

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Amount after depreciation of long-lived, physical assets used to produce goods and services and not intended for resale, classified as other.

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Property, Plant and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	$ 352,715		$ 351,792
Accumulated depreciation	(248,085)		(241,835)
Total property, plant, and equipment, net	104,630		109,957
Payments to Acquire Productive Assets [Abstract]
Non-cash capitalized interest and depreciation	(2,609)	$ (2,167)
Change in accounts payables for capital expenditures	185	1,694
Cash capital spend for the period	18,842	27,902
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	161,675		161,292
Buildings and structural components [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	173,795		173,580
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	11,740		11,740
Construction-in progress [Member] \| Stillwater Mine [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	2,731		2,615
Construction-in progress [Member] \| East Boulder Mine [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	266		435
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	2,360		$ 1,982
United States [Member]
Payments to Acquire Productive Assets [Abstract]
Capital expenditures	21,266	28,375
United States [Member] \| Stillwater Mine [Member]
Payments to Acquire Productive Assets [Abstract]
Capital expenditures	16,770	21,013
United States [Member] \| East Boulder Mine [Member]
Payments to Acquire Productive Assets [Abstract]
Capital expenditures	4,078	4,269
United States [Member] \| Other Mine [Member]
Payments to Acquire Productive Assets [Abstract]
Capital expenditures	$ 418	$ 3,093