XML 100 R81.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Bank Loans - Additional Information (Detail) € in Thousands, ¥ in Thousands, $ in Thousands | 12 Months Ended | 72 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 31, 2017 CNY (¥) | Dec. 31, 2017 USD ($) | Dec. 31, 2017 EUR (€) | Dec. 31, 2016 | Dec. 31, 2015 CNY (¥) | Dec. 31, 2017 USD ($) | Dec. 31, 2015 EUR (€)
Several Euro denominated loan |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Principal amount of loan |  |  |  |  | ¥ 12,389 |  | € 1,581
Repayments of loan | ¥ 2,795 |  | € 357 |  |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Draw downs | 326,710 | $ 50,000 |  |  |  |  |
Pledged value of bank deposit | ¥ 65,342 |  |  |  |  | $ 10,000 |
3 months EURIBOR | Several Euro denominated loan | Minimum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Variable Interest rate (as a percent) |  |  |  |  | 1.98% |  |
3 months EURIBOR | Several Euro denominated loan | Maximum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Variable Interest rate (as a percent) |  |  |  |  | 2.92% |  |
1 to 3 month LIBOR [Member] | Revolving Credit Facility [Member] | Minimum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Variable Interest rate (as a percent) | 1.50% | 1.50% | 1.50% | 1.50% |  |  |
1 to 3 month LIBOR [Member] | Revolving Credit Facility [Member] | Maximum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Variable Interest rate (as a percent) | 1.65% | 1.65% | 1.65% | 1.65% |  |  |
United States of America, Dollars | Revolving Credit Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Loan facility maximum borrowing capacity | ¥ 555,407 |  |  |  |  | 85,000 |
China, Yuan Renminbi | Revolving Credit Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Loan facility maximum borrowing capacity | ¥ 50,000 |  |  |  |  | $ 7,685 |

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 Amount of assets pledged to secure a debt instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 + Details
Name: | us-gaap_DebtInstrumentCollateralAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 Reference 2: 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=64930785&loc=d3e28551-108399 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(f)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
Name: | us-gaap_ProceedsFromLinesOfCredit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
Name: | us-gaap_RepaymentsOfLongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cmcm_SeveralEuroDenominatedLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=cmcm_ThreeMonthsEuroInterbankOfferedRateEurIBORMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=cmcm_OneMonthLondonInterbankOfferedRateLIBORMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CurrencyAxis=currency_USD
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CurrencyAxis=currency_CNY
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |