COMMITMENTS AND CONTINGENCIES - LEASES AND COMMITMENTS (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($)	Dec. 31, 2015 CNY (¥)	Dec. 31, 2013	Dec. 31, 2015 CNY (¥)
Leases, Operating [Abstract]
Total rental expense for offices	$ 12,101	¥ 78,386
Total other operating lease expenses	34,081	¥ 220,770
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2016	25,268			¥ 163,683
2017	9,575			62,023
2018	8,782			56,889
2019	8,090			52,405
2020	5,651			36,604
Thereafter	283			1,830
Total	$ 57,649			373,434
Licensing fee commitments
Licensing Fee Commitment [Abstract]
Licensing fee commitment term	2 years	2 years	3 years
Contractual Obligation, Fiscal Year Maturity [Abstract]
2016	$ 342			2,222
Total	$ 342			¥ 2,222

Licensing Fee Commitment [Abstract]

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Term of the authorization and licensing agreements the Group entered into for the right to use, redevelop and sub-license certain internet security software, in PnYnMnDTnHnMnS' format.

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No definition available.

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Expenses for the reporting period incurred under operating leases, excluding rental expenses incurred under operating leases.

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No definition available.

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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Amount of contractual obligation due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 55
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-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717

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