v2.4.1.9

SHORT-TERM BANK LOANS (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended		12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2014	Mar. 31, 2014
Loan from bank A in Taiwan [Member]
Short-term Debt [Line Items]
Amount outstanding	$ 10,000us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentOneMember	$ 15,000us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentOneMember
Interest rate spread over LIBOR		0.80%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentOneMember
Effective interest rate	1.55%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentOneMember
Loan from bank A in Taiwan [Member] | First Tranche [Member]
Short-term Debt [Line Items]
Amount outstanding	5,000us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentOneMember / us-gaap_StatementScenarioAxis = acts_DebtScenarioOneMember	10,000us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentOneMember / us-gaap_StatementScenarioAxis = acts_DebtScenarioOneMember
Interest rate spread over LIBOR	0.80%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentOneMember / us-gaap_StatementScenarioAxis = acts_DebtScenarioOneMember	0.80%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentOneMember / us-gaap_StatementScenarioAxis = acts_DebtScenarioOneMember
Debt repayment date	Mar. 31, 2015	Jan. 26, 2015
Loan from bank A in Taiwan [Member] | Second Tranche [Member]
Short-term Debt [Line Items]
Amount outstanding	5,000us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentOneMember / us-gaap_StatementScenarioAxis = acts_DebtScenarioTwoMember	5,000us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentOneMember / us-gaap_StatementScenarioAxis = acts_DebtScenarioTwoMember
Interest rate spread over LIBOR	0.80%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentOneMember / us-gaap_StatementScenarioAxis = acts_DebtScenarioTwoMember
Debt repayment date	Mar. 31, 2015	Jan. 26, 2015
Loan from bank B in Hong Kong [Member]
Short-term Debt [Line Items]
Amount outstanding	$ 11,500us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentThreeMember		$ 8,500us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentThreeMember	$ 8,500us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentThreeMember
Effective interest rate			1.15%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentThreeMember
Stated interest rate	1.36%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentThreeMember	1.25%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentThreeMember		1.84%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentThreeMember	1.28%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentThreeMember	1.24%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = acts_DebtInstrumentThreeMember
Debt repayment date	Jan. 28, 2015		Mar. 31, 2015	Dec. 31, 2013

X

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_ShortTermDebtLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, the maximum amount borrowed at any time during the period.

+ References

No definition available.

+ Details

Name:	us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	us-gaap_DebtInstrumentAxis=acts_DebtInstrumentOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=acts_DebtInstrumentThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: