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Organization and Principal Activities - Additional Information (Detail) ¥ in Thousands, $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 CNY (¥) | Dec. 31, 2017 USD ($) | Oct. 02, 2017
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member] | Exclusive technology development, support and consulting agreements |  |  |
Variable Interest Entity [Line Items] |  |  |
Minimum service fees as percentage of VIE pre-tax revenue | 20.00% | 20.00% |
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member] | Loan agreements |  |  |
Variable Interest Entity [Line Items] |  |  |
Loans granted to nominee shareholders by primary beneficiaries | ¥ 16,800 | $ 2,582 |
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member] | Shareholder voting proxy agreements |  |  |
Variable Interest Entity [Line Items] |  |  |
Shareholder voting proxy agreement effective term | 10 years | 10 years |
Period of notice to terminate the agreement | 30 days | 30 days |
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member] | Business operation agreements |  |  |
Variable Interest Entity [Line Items] |  |  |
Term of business operation agreement | 10 years | 10 years |
Chief Executive Officer and Director |  |  |
Variable Interest Entity [Line Items] |  |  |
Percentage of voting right delegated |  |  | 38.00%

X
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- Definition Represents the minimum fees to be paid to the beneficiaries as a percentage of the VIE pre-tax revenue. + References No definition available. + Details
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- Definition Percentage of voting equity interests delegated. + References No definition available. + Details
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- 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
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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