Common shares	12 Months Ended
Dec. 31, 2020
Common shares
Common shares	18. Common shares The Company’s Memorandum and Articles of Association authorizes the Company to issue 1,000,000,000 shares of USD 0.00025 par value per common share as of December 31, 2020. Each common share is entitled to one vote. The holders of common shares are also entitled to receive dividends whenever funds are legally available and when declared by the Board of Directors, which is subject to the approval by the holders of the common shares representing a majority of the aggregate voting power of all outstanding shares. As of December 31, 2019 and 2020, there were 339,165,241 and 334,401,981 common shares outstanding, respectively.

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-URI http://asc.fasb.org/topic&trid=2208762

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