Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses and Other Liabilities (Details) ¥ in Thousands, $ in Thousands	Dec. 31, 2019 CNY (¥)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 CNY (¥)
Payables And Accruals [Abstract]
Refund liability	¥ 128,478		¥ 6,625
Salary and welfare payables	113,945		124,137
Accrued service fees	69,932		94,789
Accrued marketing expenses	51,796		120,269
Accrued rental expenses			51,087
Payables to educational institutions	23,071		6,024
Other tax liabilities	15,263		29,872
Advanced deposits	11,681		6,650
Payables for leasehold improvement and intangible assets	6,818		4,911
American Depositary Receipt commission - within one year	3,526		3,482
Payables for share repurchase			857
Other payables	10,715		6,581
Total	¥ 435,225	$ 62,516	¥ 455,284

American depositary receipt commision refund current.

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Payables for leasehold improvement and intangible assets.

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Payables for share repurchase.

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Payables to educational institutions.

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Amount of obligations incurred classified as other, payable within one year or the normal operating cycle, if longer.

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Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for the marketing, trade and selling of the entity's goods and services. Marketing costs would include expenditures for planning and executing the conception, pricing, promotion, and distribution of ideas, goods, and services; costs of public relations and corporate promotions; and obligations incurred and payable for sales discounts, rebates, price protection programs, etc. offered to customers and under government programs. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for contractual rent under lease arrangements. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer, classified as current.

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Current regulatory liabilities generally represent obligations to make refunds to customers for various reasons including overpayment.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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