Name:	cmcm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisesWeightedAverageGrantDateFairValue
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Data Type:	num:perShareItemType
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The weighted average fair value of outstanding awards on share incentive plans.

No definition available.

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The measurement of exercise multiple used as an input to measure fair value of the option.

No definition available.

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The number of awards other than share options (fully vested and expected to vest) that may be exercised as of the balance sheet date.

No definition available.

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Weighted average price of awards other than options that were either exercised during the period.

No definition available.

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Weighted average price of awards other than options that were either forfeited.

No definition available.

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Weighted average per share amount at which grantees can acquire shares of common stock share based compensation plan outstanding at reporting date.

No definition available.

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- References

No definition available.

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As of the balance sheet date, the number of awards other than stock options which fully vested and expected to vest under share-based compensation plan.

No definition available.

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Weighted average per share amount at which grantees can acquire shares of common stock share based compensation plan.

No definition available.

Name:	cmcm_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOtherThanOptionsGrantsInPeriodWeightedAverageExercisePrice
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- References

No definition available.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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Data Type:	num:perShareItemType
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

No definition available.

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Data Type:	num:percentItemType
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The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

No definition available.

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Data Type:	num:percentItemType
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The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

No definition available.

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Data Type:	num:percentItemType
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The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

No definition available.

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Data Type:	num:percentItemType
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Number of non-option equity instruments exercised by participants.

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Data Type:	xbrli:sharesItemType
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Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.

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Net number of non-option equity instruments granted to participants.

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Data Type:	xbrli:stringItemType
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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Data Type:	num:perShareItemType
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Price of a single share of a number of saleable stocks of a company.

No definition available.

Name:	us-gaap_SharePrice
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- References

No definition available.

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Data Type:	xbrli:stringItemType
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Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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