Commitments and Contingencies, Tax Matters (Details)	12 Months Ended
Dec. 31, 2011
Income Tax Uncertainties [Abstract]
Significant change in unrecognized tax benefits	We do not expect our unrecognized tax benefits to change significantly over the next twelve months.

This element provides a description of the nature and other information deemed necessary to provide an understanding of the uncertain tax position or contingency giving rise to the significant expected increase or decrease within twelve months of the reporting date in the related unrecognized tax benefit.

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

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 48

-Paragraph 21

-Subparagraph d(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration