CONSOLIDATED BALANCE SHEETS (Parenthetical) ¥ in Thousands, $ in Thousands	Dec. 31, 2018 CNY (¥) shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 CNY (¥) shares	Dec. 31, 2017 USD ($) $ / shares shares
Convertible Debt, Current	¥ 6,863	$ 998	¥ 0
Accounts payable	114,589	16,666	76,351
Deferred revenue	951,616	138,407	758,044
Advances from customers	101,690	14,790	80,406
Income taxes payable	235,561	34,261	146,298
Accrued liabilities and other current liabilities	2,414,371	351,156	1,465,963
Amounts due to related parties	28,336	4,121	30,502
Short-term Debt	0	0	588,235
Convertible Debt, Noncurrent	0	0	6,536
Deferred revenue	91,710	13,339	57,718
Deferred tax liabilities	¥ 27,505	$ 4,000	¥ 10,810
Class A common shares [Member]
Common stock, par value (in dollars per share) \| $ / shares		$ 0.00001		$ 0.00001
Common shares, shares authorized \| shares	10,000,000,000	10,000,000,000	10,000,000,000	10,000,000,000
Common shares, shares issued \| shares	981,740,848	981,740,848	945,245,908	945,245,908
Common shares, shares outstanding \| shares	981,740,848	981,740,848	945,245,908	945,245,908
Class B common shares [Member]
Common stock, par value (in dollars per share) \| $ / shares		$ 0.00001		$ 0.00001
Common shares, shares authorized \| shares	1,000,000,000	1,000,000,000	1,000,000,000	1,000,000,000
Common shares, shares issued \| shares	288,182,976	288,182,976	317,982,976	317,982,976
Common shares, shares outstanding \| shares	288,182,976	288,182,976	317,982,976	317,982,976
Variable interest entity [Member]
Convertible Debt, Current	¥ 0		¥ 0
Accounts payable	112,167		67,817
Deferred revenue	950,816		757,244
Advances from customers	101,690		80,406
Income taxes payable	162,118		142,204
Accrued liabilities and other current liabilities	2,207,138		1,404,877
Amounts due to related parties	28,336		30,502
Short-term Debt	0		0
Convertible Debt, Noncurrent	0		0
Deferred revenue	86,977		52,185
Deferred tax liabilities	¥ 0		¥ 8,404

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. 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 amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

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Face amount or stated value per share of common stock.

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The portion of the carrying value of long-term convertible debt as of the balance sheet date that is scheduled to be repaid within one year or in the normal operating cycle if longer. Convertible debt is a financial instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

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The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

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