Concentration Risk, Number of Financial Institutions

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Contract With Customer, Term Of Contract

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Deferred Rent And Early Lease Termination Liabilities

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Number of Consolidated Variable Interest Entities

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Revenue, Performance Obligation, Description Of Timing, Substantially All Performance Period

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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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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of lessee's right to use underlying asset under operating lease.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)	1 Months Ended	12 Months Ended
	Jun. 30, 2018 entity	Dec. 31, 2019 USD ($) financial_institution entity	Dec. 31, 2018 USD ($)	Jan. 01, 2019 USD ($)
Concentration Risk [Line Items]
Number of consolidated VIEs \| entity	1	4
Operating lease asset		$ 4,359,000
Operating lease liabilities, long-term		$ 4,650,000
Term of contract		1 year
Investments, other than temporary impairment		$ 0	$ 0
Software Development Costs
Concentration Risk [Line Items]
Estimated useful life		3 years
Cash Concentration Risk \| Cash
Concentration Risk [Line Items]
Percentage of cash		80.00%
Number of financial institutions \| financial_institution		2
Advertising and Other
Concentration Risk [Line Items]
Performance period for substantially all obligations		1 year
Accounting Standards Update 2016-02
Concentration Risk [Line Items]
Operating lease asset				$ 4,900,000
Short-term				1,100,000
Operating lease liabilities, long-term				5,700,000
Deferred rent and early lease termination liabilities				$ (3,300,000)
KanKan
Concentration Risk [Line Items]
Term of contract		1 year