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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%

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