Deferred Costs - Schedule of Movements of Deferred Costs (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2019 CNY (¥)	Dec. 31, 2018 CNY (¥)	Dec. 31, 2019 USD ($)
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Beginning balances (current and non-current)	¥ 327,267	¥ 98,260
Additions	440,495	374,594
Amortizations	(318,693)	(145,488)
Impairments	(134)	(99)
Ending balances (current and non-current)	448,935	327,267
Deferred costs, current	243,447	180,657	$ 34,969
Deferred costs, non-current	¥ 205,488	¥ 146,610	$ 29,517

Amount of deferred cost, excluding capitalized cost related to contract with customer; classified as noncurrent.

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Sum of the carrying amounts as of the balance sheet date of deferred costs capitalized at the end of the reporting period that are expected to be charged against earnings within one year or the normal operating cycle, if longer.

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Amount of impairment loss for deferred sales inducement cost.

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Amount of deferred sale inducement cost capitalized.

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Amount of amortization expense (reversal of expense) for deferred sales inducement cost.

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Amount of deferred sale inducement cost capitalized on contract remaining in force.

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