STOCKHOLDERS' EQUITY - GSR Agreement (Details) - USD ($) $ / shares in Units, $ in Millions	May 08, 2019	May 06, 2019
tZero.com, Inc.
Class of Stock [Line Items]
Sale of Stock, Number of Shares Issued in Transaction	508,710
Number of shares sold in transaction as percentage of total shares issued and outstanding	0.50%
Total consideration received from sale of stock	$ 5.0
tZero.com, Inc. \| GSR Capital [Member]
Class of Stock [Line Items]
Cash portion of acquisition price		$ 30.0
Sale of tokens (in usd per token)		$ 6.67

Sale Of Stock, Number of Shares Issued In Transaction As A Percentage Of Total Shares Issued And Outstanding

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- Definition

Sale Of Stock, Total Consideration Received On Transaction

+ References

No definition available.

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- Definition

Sale Of Tokens, Price Per Token

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

The cash outflow associated with the purchase of or advances to an 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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