SIGNIFICANT ACCOUNTING POLICIES - Property and Equipment, net (Details)	12 Months Ended
Dec. 31, 2019
Computers and equipment
PROPERTY AND EQUIPMENT, NET
Residual rate (as a percent)	5.00%
Computers and equipment \| Minimum
PROPERTY AND EQUIPMENT, NET
Estimated useful lives	P3Y
Computers and equipment \| Maximum
PROPERTY AND EQUIPMENT, NET
Estimated useful lives	P5Y
Furniture and fixtures
PROPERTY AND EQUIPMENT, NET
Residual rate (as a percent)	5.00%
Furniture and fixtures \| Minimum
PROPERTY AND EQUIPMENT, NET
Estimated useful lives	P3Y
Furniture and fixtures \| Maximum
PROPERTY AND EQUIPMENT, NET
Estimated useful lives	P5Y
Office equipment
PROPERTY AND EQUIPMENT, NET
Residual rate (as a percent)	5.00%
Office equipment \| Minimum
PROPERTY AND EQUIPMENT, NET
Estimated useful lives	P3Y
Office equipment \| Maximum
PROPERTY AND EQUIPMENT, NET
Estimated useful lives	P5Y
Vehicle
PROPERTY AND EQUIPMENT, NET
Estimated useful lives	P5Y
Residual rate (as a percent)	5.00%
Office building
PROPERTY AND EQUIPMENT, NET
Estimated useful lives	P30Y
Residual rate (as a percent)	5.00%

Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 35
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68071081&loc=d3e1205-110223

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790

Name:	us-gaap_PropertyPlantAndEquipmentEstimatedUsefulLives
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration