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Goodwill - Additional Information (Detail) ¥ in Thousands, $ in Thousands	Sep. 30, 2020 CNY (¥)	Sep. 30, 2020 USD ($)	Dec. 31, 2019 CNY (¥)	Jul. 15, 2017
Indefinite-lived Intangible Assets [Line Items]
Goodwill	¥ 162,574	$ 23,945	¥ 162,574
Goodwill, accumulated impairment loss	¥ 0		¥ 0
Tasgen Group [Member]
Indefinite-lived Intangible Assets [Line Items]
Voting Interests Acquired				66.67%

X

- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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