Income Taxes Income Taxes (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Income Tax Disclosure [Abstract]
Unrecognized tax benefits, period increase (decrease)	$ 87,000	$ 2,133,000
Income tax expense	2,397,000us-gaap_IncomeTaxExpenseBenefit	4,211,000us-gaap_IncomeTaxExpenseBenefit
Document Period End Date	Mar. 31, 2015
UNITED KINGDOM
Income Tax Disclosure [Abstract]
Operating Loss Carryforwards	$ 41,400,000

The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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

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The net amount of all increases and decreases in unrecognized tax benefits for the period.

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

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-Name Accounting Standards Codification

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