INVESTMENTS AND FAIR VALUE MEASUREMENT - Schedule of Financial Asset and Liabilities Measured At Fair Value On a Recurring Basis (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Assets
Deposits with clearing organizations	$ 338.0	$ 186.0
Asset related to user cryptocurrencies safeguarding obligation	14,708.0	8,431.0
Liabilities
User cryptocurrencies safeguarding obligation	14,708.0	8,431.0
U.S. Treasury securities
Assets
Deposits with clearing organizations	50.0
Fair Value, Recurring
Assets
Total financial assets	17,028.0	10,181.0
Liabilities
Total financial liabilities	16,300.0	9,428.0
Fair Value, Recurring \| U.S. Treasury securities
Assets
Deposits with clearing organizations	50.0
Fair Value, Recurring \| Equity securities - securities owned
Assets
Other current assets	10.0	8.0
Fair Value, Recurring \| Commercial paper
Assets
Other current assets		5.0
Fair Value, Recurring \| Government bonds
Assets
Other current assets		3.0
Fair Value, Recurring \| Corporate bonds
Assets
Other current assets		2.0
Fair Value, Recurring \| Asset related to user cryptocurrencies safeguarding obligation
Assets
Asset related to user cryptocurrencies safeguarding obligation	14,708.0	8,431.0
Fair Value, Recurring \| Stablecoin
Assets
Other current assets	20.0
Fair Value, Recurring \| Money market funds - escrow account
Assets
Other current assets	2.0
Fair Value, Recurring \| User-held fractional shares
Assets
Other current assets	1,592.0	997.0
Fair Value, Recurring \| User cryptocurrencies safeguarding obligation
Liabilities
User cryptocurrencies safeguarding obligation	14,708.0	8,431.0
Fair Value, Recurring \| Fractional shares repurchase obligations
Liabilities
Other current liabilities	1,592.0	997.0
Fair Value, Recurring \| Time deposit
Assets
Cash equivalents	500.0
Fair Value, Recurring \| Money market funds
Assets
Cash equivalents	146.0	735.0
Fair Value, Recurring \| Level 1
Assets
Total financial assets	1,820.0	1,743.0
Liabilities
Total financial liabilities	1,592.0	997.0
Fair Value, Recurring \| Level 1 \| U.S. Treasury securities
Assets
Deposits with clearing organizations	50.0
Fair Value, Recurring \| Level 1 \| Equity securities - securities owned
Assets
Other current assets	10.0	8.0
Fair Value, Recurring \| Level 1 \| Commercial paper
Assets
Other current assets		0.0
Fair Value, Recurring \| Level 1 \| Government bonds
Assets
Other current assets		3.0
Fair Value, Recurring \| Level 1 \| Corporate bonds
Assets
Other current assets		0.0
Fair Value, Recurring \| Level 1 \| Asset related to user cryptocurrencies safeguarding obligation
Assets
Asset related to user cryptocurrencies safeguarding obligation	0.0	0.0
Fair Value, Recurring \| Level 1 \| Stablecoin
Assets
Other current assets	20.0
Fair Value, Recurring \| Level 1 \| Money market funds - escrow account
Assets
Other current assets	2.0
Fair Value, Recurring \| Level 1 \| User-held fractional shares
Assets
Other current assets	1,592.0	997.0
Fair Value, Recurring \| Level 1 \| User cryptocurrencies safeguarding obligation
Liabilities
User cryptocurrencies safeguarding obligation	0.0	0.0
Fair Value, Recurring \| Level 1 \| Fractional shares repurchase obligations
Liabilities
Other current liabilities	1,592.0	997.0
Fair Value, Recurring \| Level 1 \| Time deposit
Assets
Cash equivalents	0.0
Fair Value, Recurring \| Level 1 \| Money market funds
Assets
Cash equivalents	146.0	735.0
Fair Value, Recurring \| Level 2
Assets
Total financial assets	15,208.0	8,438.0
Liabilities
Total financial liabilities	14,708.0	8,431.0
Fair Value, Recurring \| Level 2 \| U.S. Treasury securities
Assets
Deposits with clearing organizations	0.0
Fair Value, Recurring \| Level 2 \| Equity securities - securities owned
Assets
Other current assets	0.0	0.0
Fair Value, Recurring \| Level 2 \| Commercial paper
Assets
Other current assets		5.0
Fair Value, Recurring \| Level 2 \| Government bonds
Assets
Other current assets		0.0
Fair Value, Recurring \| Level 2 \| Corporate bonds
Assets
Other current assets		2.0
Fair Value, Recurring \| Level 2 \| Asset related to user cryptocurrencies safeguarding obligation
Assets
Asset related to user cryptocurrencies safeguarding obligation	14,708.0	8,431.0
Fair Value, Recurring \| Level 2 \| Stablecoin
Assets
Other current assets	0.0
Fair Value, Recurring \| Level 2 \| Money market funds - escrow account
Assets
Other current assets	0.0
Fair Value, Recurring \| Level 2 \| User-held fractional shares
Assets
Other current assets	0.0	0.0
Fair Value, Recurring \| Level 2 \| User cryptocurrencies safeguarding obligation
Liabilities
User cryptocurrencies safeguarding obligation	14,708.0	8,431.0
Fair Value, Recurring \| Level 2 \| Fractional shares repurchase obligations
Liabilities
Other current liabilities	0.0	0.0
Fair Value, Recurring \| Level 2 \| Time deposit
Assets
Cash equivalents	500.0
Fair Value, Recurring \| Level 2 \| Money market funds
Assets
Cash equivalents	0.0	0.0
Fair Value, Recurring \| Level 3
Assets
Total financial assets	0.0	0.0
Liabilities
Total financial liabilities	0.0	0.0
Fair Value, Recurring \| Level 3 \| U.S. Treasury securities
Assets
Deposits with clearing organizations	0.0
Fair Value, Recurring \| Level 3 \| Equity securities - securities owned
Assets
Other current assets	0.0	0.0
Fair Value, Recurring \| Level 3 \| Commercial paper
Assets
Other current assets		0.0
Fair Value, Recurring \| Level 3 \| Government bonds
Assets
Other current assets		0.0
Fair Value, Recurring \| Level 3 \| Corporate bonds
Assets
Other current assets		0.0
Fair Value, Recurring \| Level 3 \| Asset related to user cryptocurrencies safeguarding obligation
Assets
Asset related to user cryptocurrencies safeguarding obligation	0.0	0.0
Fair Value, Recurring \| Level 3 \| Stablecoin
Assets
Other current assets	0.0
Fair Value, Recurring \| Level 3 \| Money market funds - escrow account
Assets
Other current assets	0.0
Fair Value, Recurring \| Level 3 \| User-held fractional shares
Assets
Other current assets	0.0	0.0
Fair Value, Recurring \| Level 3 \| User cryptocurrencies safeguarding obligation
Liabilities
User cryptocurrencies safeguarding obligation	0.0	0.0
Fair Value, Recurring \| Level 3 \| Fractional shares repurchase obligations
Liabilities
Other current liabilities	0.0	0.0
Fair Value, Recurring \| Level 3 \| Time deposit
Assets
Cash equivalents	0.0
Fair Value, Recurring \| Level 3 \| Money market funds
Assets
Cash equivalents	$ 0.0	$ 0.0

Fair value of asset to safeguard crypto-asset held for platform user.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section FF
-Subsection Q1
-Publisher SEC

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-Number Topic 5
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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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