Related party transactions - Schedule of Significant Related Party Transactions (Details) - CNY (¥) ¥ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related party transactions [Line Items]
Loan to related parties	¥ 170,000	¥ 188,000	¥ 24,962
Promotion expense charged from Related parties	26,462	0	0
Payment on behalf of related parties, net of repayments	3,866	(2,543)	(23,116)
Repayment of loans from related parties	0	20,000	35,462
Online games revenue [Member]
Related party transactions [Line Items]
Revenue shared from related parties	3,588	31,366	87,414
Guangzhou Chenjun
Related party transactions [Line Items]
Partial disposal of investments to Guangzhou Chenjun	0	0	35,160
Guangzhou Sunhongs \| Bandwidth service [Member]
Related party transactions [Line Items]
Expense with related party	116,033	103,439	92,068
Other Related Party [Member]
Related party transactions [Line Items]
Other transaction with related parties	23,447	11,833	14,276
Kingsoft Group
Related party transactions [Line Items]
Purchase of fixed assets from Kingsoft Group	16,776	0	0
Kingsoft Group \| Bandwidth service [Member]
Related party transactions [Line Items]
Expense with related party	¥ 47,929	¥ 11,314	¥ 711

The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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-Section 45
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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The cash outflow for the payment of a long-term borrowing made from a related party where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Payments for Advances from Affiliates.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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The cash outflow associated with payment on behalf of a related party, net of repayments.

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Cash outflow related to payments of loan to related parties.

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Represents the amount of promotion expense charged from Related parties.

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Represents the amount of other transaction with related parties during the reporting period.

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Purchases of fixed assets from related party.

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