v2.4.1.9

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Narrative) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Summary Of Accounting Policies [Line Items]
Fair value change in trading securities			$ 2us-gaap_TradingSecuritiesUnrealizedHoldingGainLoss
Impairment charge	0us-gaap_AssetImpairmentCharges	0us-gaap_AssetImpairmentCharges	0us-gaap_AssetImpairmentCharges
Impairment recognized in respect of other investments		681us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet	2,543us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet
Land expense	36acts_LandUseRightExpense	36acts_LandUseRightExpense	36acts_LandUseRightExpense
Utilization of subsidy from local authorities of Zhuhai, the People's Republic of China (the "PRC")		1,068us-gaap_OtherNoncashIncome	674us-gaap_OtherNoncashIncome
Number of shares repurchased	70,774,015us-gaap_StockRepurchasedDuringPeriodShares	11,772,294us-gaap_StockRepurchasedDuringPeriodShares	14,812,056us-gaap_StockRepurchasedDuringPeriodShares
Allowance for doubtful accounts receivable	558us-gaap_ProvisionForDoubtfulAccounts
Allowances for doubtful accounts receivable written down	558us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs		(621)us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs
Advertising expenses	604us-gaap_AdvertisingExpense	666us-gaap_AdvertisingExpense	106us-gaap_AdvertisingExpense
Share-based compensation	45us-gaap_ShareBasedCompensation	492us-gaap_ShareBasedCompensation	1,465us-gaap_ShareBasedCompensation
Cost of revenue [Member]
Summary Of Accounting Policies [Line Items]
Share-based compensation	28us-gaap_ShareBasedCompensation / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember	49us-gaap_ShareBasedCompensation / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember	10us-gaap_ShareBasedCompensation / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember
Research and development expenses [Member]
Summary Of Accounting Policies [Line Items]
Share-based compensation	10us-gaap_ShareBasedCompensation / us-gaap_IncomeStatementLocationAxis = us-gaap_ResearchAndDevelopmentExpenseMember	347us-gaap_ShareBasedCompensation / us-gaap_IncomeStatementLocationAxis = us-gaap_ResearchAndDevelopmentExpenseMember	1,091us-gaap_ShareBasedCompensation / us-gaap_IncomeStatementLocationAxis = us-gaap_ResearchAndDevelopmentExpenseMember
General and administrative expenses [Member]
Summary Of Accounting Policies [Line Items]
Share-based compensation	5us-gaap_ShareBasedCompensation / us-gaap_IncomeStatementLocationAxis = us-gaap_GeneralAndAdministrativeExpenseMember	79us-gaap_ShareBasedCompensation / us-gaap_IncomeStatementLocationAxis = us-gaap_GeneralAndAdministrativeExpenseMember	312us-gaap_ShareBasedCompensation / us-gaap_IncomeStatementLocationAxis = us-gaap_GeneralAndAdministrativeExpenseMember
Selling and marketing expenses [Member]
Summary Of Accounting Policies [Line Items]
Share-based compensation	$ 2us-gaap_ShareBasedCompensation / us-gaap_IncomeStatementLocationAxis = us-gaap_SellingAndMarketingExpenseMember	$ 17us-gaap_ShareBasedCompensation / us-gaap_IncomeStatementLocationAxis = us-gaap_SellingAndMarketingExpenseMember	$ 52us-gaap_ShareBasedCompensation / us-gaap_IncomeStatementLocationAxis = us-gaap_SellingAndMarketingExpenseMember
Dutch auction tender offer [Member]
Summary Of Accounting Policies [Line Items]
Number of shares repurchased	60,001,062us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = acts_DutchAuctionTenderOfferMember
Minimum [Member]
Summary Of Accounting Policies [Line Items]
Useful economic lives of purchased software and technology licenses	1 year
Maximum [Member]
Summary Of Accounting Policies [Line Items]
Useful economic lives of purchased software and technology licenses	9 years

X

- Definition

Prepaid leasehold land is expensed on a straight-line basis over the respective term of the right to use the land.

+ References

No definition available.

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 720

-SubTopic 35

-Section 50

-Paragraph 1

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- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

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-SubTopic 10

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-SubTopic 10

-Section S99

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Other income or gains included in net income that result in no cash inflows or outflows in the period and are not separately disclosed.

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-Section 45

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X

- Definition

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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- Definition

Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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-Name Regulation S-X (SX)

-Number 210

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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- Definition

Amount of unrealized holding gain (loss) recognized in the income statement for investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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