Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Reconciliation of provision for (benefit from) income taxes
Provision for (benefit from) income taxes at U.S. Federal statutory rate	$ 4,071	$ 1,904	$ (3,407)
State taxes	1,053	(469)	(1,661)
Differential in rates on foreign earnings	(9,924)	(1,842)	(1,768)
Losses for which no benefit is taken	9,185	6,880	8,980
Change in valuation allowance	0	(450)	8,150
Change in liabilities for uncertain tax positions	(1,540)	1,261	2,390
Non-deductible stock-based compensation	1,882	1,940	1,811
Research credits	(2,138)	(1,404)	(1,163)
Non-deductible acquisition related expenses	0	1,289
Other	265	665	1,072
Total	$ 2,854	$ 9,774	$ 14,404

Income tax reconciliation change liabilities for uncertain tax positions.

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Income tax reconciliation for losses.

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Income tax reconciliation nondeductible expense acquisition.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to pretax Income or Loss from continuing operations; income tax expense or benefit may include interest and penalties on tax uncertainties based on the entity's accounting policy.

+ References

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

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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.

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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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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 research tax credits generated or utilized under enacted tax laws during the period.

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