Commitments and Contingencies (Details) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2012 USD ($)	Sep. 30, 2012 Pending or Threatened Litigation [Member] USD ($)	Sep. 30, 2012 Pending or Threatened Litigation [Member] GBP (£)
Loss Contingencies [Line Items]
Damages sought, amount		$ 8,900	£ 5,500
Damages sought, interest at statutory rate (per annum)		8.00%	8.00%
IRS proposed adjustments to tax years 2000 through 2002, before penalty and interest	$ 16,500
Potential penalty, percentage of tax assessment	20.00%

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

+ Details