RELATED PARTY TRANSACTIONS, Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Abstract]
Amounts due from related parties, current	$ 19,449	$ 4,735
Amounts due to related parties, current	42,613	34,990
Tencent [Member]
Related Party Transaction [Abstract]
Royalty fee and license fee to	110,686	122,234	$ 96,713
Services provided by	23,352	19,005	13,066
Issuance of convertible notes to	0	0	50,000
Interest expense to	0	563	2,092
Conversion of convertible notes (principal amount) by	0	100,000	$ 0
Amounts due from related parties, current	553	477
Amounts due to related parties, current	$ 38,416	$ 34,970

Amount representing proceeds through notes conversion by related party.

No definition available.

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- Definition

Represents the expenses for royalty and license fees.

+ References

No definition available.

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- Definition

The Related Party Service Fees.

+ References

No definition available.

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- Definition

The aggregate amount of receivables to be collected from related parties 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, at the financial statement date. which are usually due within one year (or one business cycle).

+ References

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- Definition

Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of interest expense incurred on a debt or other obligation to related party.

+ References

No definition available.

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- Definition

The cash inflow from a long-term borrowing made from related parties 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: Proceeds from Advances from Affiliates.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 14
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- References

No definition available.

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