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- Definition

Payments to Acquire Productive Assets, Depreciation and Interest Costs Capitalized, and Capital Expenditures Incurred But Not Yet Paid

+ References

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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

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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)

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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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- 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.

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Property, Plant and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	$ 348,385		$ 348,385		$ 337,832
Accumulated depreciation	(235,558)		(235,558)		(218,951)
Total property, plant, and equipment, net	112,827		112,827		118,881
Payments to Acquire Productive Assets [Abstract]
Non-cash capitalized interest / depreciation			(6,756)	$ (6,228)
Change in accounts payables for capital expenditures			1,777	(431)
Cash capital spend for the period	25,168	$ 33,258	83,386	87,038
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	159,792		159,792		152,421
Buildings and structural components [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	173,265		173,265		169,609
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	11,740		11,740		9,488
Construction-in progress [Member] \| Stillwater Mine [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	953		953		2,633
Construction-in progress [Member] \| East Boulder Mine [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	569		569		1,539
Construction-in progress [Member] \| Marathon Property [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	148		148		148
Construction-in progress [Member] \| Processing Facilities and Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	$ 1,918		1,918		$ 1,994
United States [Member]
Payments to Acquire Productive Assets [Abstract]
Capital expenditures			88,319	93,695
United States [Member] \| Stillwater Mine [Member]
Payments to Acquire Productive Assets [Abstract]
Capital expenditures			70,172	69,513
United States [Member] \| East Boulder Mine [Member]
Payments to Acquire Productive Assets [Abstract]
Capital expenditures			13,548	21,189
United States [Member] \| Other Mine [Member]
Payments to Acquire Productive Assets [Abstract]
Capital expenditures			4,599	2,993
Foreign [Member]
Payments to Acquire Productive Assets [Abstract]
Capital expenditures			$ 46	$ 2