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Share-based Payment Arrangements - Summary of Information About USISH Option Plans (Detail) | 8 Months Ended | 12 Months Ended
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Dec. 31, 2018 shares $ / shares ¥ / shares | Dec. 31, 2019 shares $ / shares ¥ / shares | Dec. 31, 2019 shares ¥ / shares | Dec. 31, 2018 shares $ / shares ¥ / shares | Dec. 31, 2018 shares ¥ / shares | Dec. 31, 2017 shares ¥ / shares
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |  |  |  |  |
Weighted average exercise price, Beginning balance | $ / shares |  | $ 58.1 |  |  |  |
Weighted average exercise price options granted | $ / shares | $ 56.4 |  |  |  |  |
Weighted average exercise price, Options forfeited | $ / shares | 71.5 |  |  |  |  |
Weighted average exercise price, Ending balance | $ / shares | $ 58.1 |  |  | $ 58.1 |  |
USISH option plans [member] |  |  |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |  |  |  |  |
Number of options, beginning balance |  | 21,537,000 | 21,537,000 | 22,341,000 | 22,341,000 | 24,997,000
Number of options, granted |  | 23,323,000 | 23,323,000 |  |  |
Number of options, exercised |  | (3,164,000) | (3,164,000) |  |  |
Number of options, forfeited |  | (463,000) | (463,000) | (804,000) | (804,000) | (2,656,000)
Number of options, Ending balance | 21,537,000 | 41,233,000 | 41,233,000 | 21,537,000 | 21,537,000 | 22,341,000
Number of options, exercisable, end of year | 12,884,000 | 13,694,000 | 13,694,000 | 12,884,000 | 12,884,000 | 8,896,000
Weighted average exercise price, Beginning balance | ¥ / shares |  |  | ¥ 15.5 |  | ¥ 15.5 | ¥ 15.5
Weighted average exercise price options granted | ¥ / shares |  |  | 13.3 |  |  |
Weighted average exercise price options exercised | ¥ / shares |  |  | 15.5 |  |  |
Weighted average exercise price, Options forfeited | ¥ / shares |  |  | 15.4 |  | 15.5 | 15.5
Weighted average exercise price, Ending balance | ¥ / shares |  |  | 14.3 |  | 15.5 | 15.5
Weighted average exercise price, Options exercisable, end of year | ¥ / shares | $ 15.5 | $ 15.5 | ¥ 15.5 | $ 15.5 | ¥ 15.5 | ¥ 15.5
USISH option plans [member] | Bottom of range [member] |  |  |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |  |  |  |  |
Fair value of options granted (CNY) |  | 6.27 | 6.27 |  |  |
USISH option plans [member] | Top of range [member] |  |  |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |  |  |  |  |
Fair value of options granted (CNY) |  | 13.47 | 13.47 |  |  |

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