Derivative Instruments (Details) (USD $) In Millions, unless otherwise specified		3 Months Ended
Jun. 30, 2011	Dec. 31, 2011 Platinum [Member] oz	Sep. 30, 2011 Platinum [Member] oz	Dec. 31, 2011 Palladium [Member] oz	Sep. 30, 2011 Palladium [Member] oz	Dec. 31, 2011 Rhodium [Member] oz	Sep. 30, 2011 Rhodium [Member] oz
Derivative outstanding	$ 0
Ounces		564	25,028	676	37,258	1,258	5,643
Average Price		1,711	1,794	745	763	2,055	2,211
Margin deposits outstanding	$ 0

Fair value as of the balance sheet date of price risk derivative assets, net of price risk derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 17
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13433-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13495-108611

Name:	us-gaap_PriceRiskDerivativesAtFairValueNet
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant