Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 35,208us-gaap_ProfitLoss	$ (22,055)us-gaap_ProfitLoss	$ 30,445us-gaap_ProfitLoss
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments, net of tax benefit (expense)	(13,899)	3,325	3,902
Actuarial (losses) gains related to defined benefit pension plans, net of tax benefit (expense) of $2,826 in 2014, $(1,210) in 2013 and $2,628 in 2012	(6,309)	2,913	(6,778)
Unrealized holding (losses) gains on investments arising during period, net of tax benefit	(771)us-gaap_UnrealizedGainLossOnInvestments	147us-gaap_UnrealizedGainLossOnInvestments	(946)us-gaap_UnrealizedGainLossOnInvestments
Reclassification adjustment for other-than-temporary impairment in value of investments, net of tax benefit	0	0	786
Other comprehensive (loss) income	(20,979)	6,385	(3,036)
Total comprehensive income (loss)	14,229	(15,670)	27,409
Less: net income attributable to noncontrolling interest, net of taxes	(3,013)	0	0
Comprehensive income (loss) attributable to Atmel	$ 11,216us-gaap_ComprehensiveIncomeNetOfTax	$ (15,670)us-gaap_ComprehensiveIncomeNetOfTax	$ 27,409us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Amount after tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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