Income Taxes Reconciliation of Statutory Federal Tax Rates and Effective Tax Rates (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Effective Income Tax Rate, Continuing Operations	0.00%	0.00%	0.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate	0.00%	0.00%	0.00%
Income Tax Reconciliation, Income Tax Expense (Benefit), at Federal Statutory Income Tax Rate	$ (14,309)	$ (4,431)	$ (299)
Effective Income Tax Rate Reconciliation, State and Local Income Taxes	0.00%	0.00%	0.00%
Income Tax Reconciliation, Repatriation of Foreign Earnings	6,754	0	0
Income Tax Reconciliation, Foreign Income Tax Rate Differential	(2,796)	(2,888)	(2,886)
Income Tax Reconciliation, State and Local Income Taxes	(266)	(131)	(132)
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings	0.00%	0.00%	0.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses	0.00%	0.00%	0.00%
Income Tax Reconciliation, Change in Deferred Tax Assets Valuation Allowance	3,725	(5,524)	1,173
Income Tax Reconciliation, Nondeductible Expense, Impairment Losses	9,377	(81)	(251)
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance	0.00%	0.00%	0.00%
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential	0.00%	0.00%	0.00%
Effective Income Tax Rate Reconciliation, Tax Credits	0.00%	0.00%	0.00%
Income Tax Reconciliation, Tax Credits	(304)	(737)	142
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost	0.00%	0.00%	0.00%
Income Tax Reconciliation, Earn Out Liability	(1,768)	0	0
Income Tax Reconciliation, Nondeductible Expense, Share-based Compensation Cost	1,812	1,275	1,528
Effective Income Tax Rate Reconciliation, Other Adjustments	0.00%	0.00%	0.00%
Income Tax Reconciliation, Other Adjustments	365	202	240
Income Tax Expense (Benefit)	2,590	(11,132)	(485)
Acquisition-related Costs [Member]
Effective Income Tax Rate Reconciliation, Other Adjustments	0.00%	0.00%	0.00%
Income Tax Reconciliation, Transaction Costs	$ 0	$ 1,183	$ 0

Income Tax Reconciliation, Earn Out Liability

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Income Tax Reconciliation, Transaction Costs

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- Definition

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Topic 235

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The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

-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.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to changes in the valuation allowance for deferred tax assets.

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-Publisher FASB

-Name Accounting Standards Codification

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the difference between statutory income tax rates in foreign jurisdictions and the domestic federal statutory income tax rate recorded during the period.

+ References

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to nondeductible impairment losses under enacted tax laws.

+ References

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to differences in the deductibility or nondeductibility of incentive stock options and other equity-based compensation costs in accordance with generally accepted accounting principles and enacted tax laws.

+ References

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to the repatriation of foreign earnings under enacted tax laws.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the state and local income tax expense or benefit, net of the federal tax benefit (expense) thereon, recorded during the period.

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The sum of the differences between the effective income tax rate and domestic federal statutory income tax rate that can be explained by all tax credits generated or utilized under enacted tax laws during the period.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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-Publisher FASB

-Name Accounting Standards Codification

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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.

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-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to changes in the valuation allowance for deferred tax assets in the period.

+ References

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

-Publisher FASB

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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.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to total foreign income tax expense or benefit. The foreign income tax expense or benefit difference represents the income tax expense or benefit at applicable domestic statutory income tax rates applied to foreign earnings or loss for the period versus the foreign income tax expense or benefit calculated by applying the appropriate foreign tax rates.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

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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.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to nondeductible impairment losses under enacted tax laws.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to differences in the deductibility of incentive stock options and other equity-based compensation costs in accordance with generally accepted accounting principles and enacted tax laws.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the year/accounting period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to the repatriation of foreign earnings in the period.

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The sum of the differences between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to tax credits.

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