Acquisition Of Shares Under Securities Purchase Agreement

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Additional True-Up Common Stock Consideration Liability At Fair Value in accordance with ASC 480

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Additional True Up Common Stock Consideration considered as Liability At Fair Value Remeasured

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Represents amount of Noncontrolling interest of the acquisition date.

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Gain (Loss) On Remeasurement Of True-Up Common Stock Consideration considered as Liability

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Maximum Stock Price Consideration For Additional Shares

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Number Of Companies Operated By DBOT

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Number of shares of equity interests issued or issuable to acquire entity.

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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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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Amount of assets acquired at the acquisition date.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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The amount of financial assets (as defined) recognized as of the acquisition date.

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The amount of financial liabilities assumed (as defined) which have been recognized as of the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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Amount of realized and unrealized gain (loss), from the firm's direct investment activity, conducted separately from customer trading activities, and includes, but is not limited to, investments in private equity, alternative investment products, real estate, and exchanges and memberships.

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Per share or per unit amount of equity securities issued.

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Acquisitions and Divestitures - Delaware Board of Trade Holdings, Inc. (Details) $ / shares in Units, shares in Millions		1 Months Ended		3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2019 shares	Jul. 31, 2019 USD ($) $ / shares shares	Apr. 30, 2019 $ / shares shares	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) company shares	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Acquisitions and Divestitures
Number of common stock issued \| shares	0.6
DBOT
Acquisitions and Divestitures
Shares in DBOT \| shares		2.2	6.9
Number of common stock issued \| shares		1.4	4.4			13.1
Shares issued, price per share (in dollars per share) \| $ / shares		$ 2.11	$ 2.11
Percentage of voting equity interests acquired		99.00%		37.00%		37.00%
Maximum Stock Price Consideration For Additional Shares \| $ / shares		$ 2.11
Liability at Fair value		$ 2,200,000		$ 800,000		$ 800,000
Liability Remeasured								$ 7,300,000
Loss on Remeasurement				0		1,500,000		5,100,000
Investment fair value				3,100,000		3,100,000
Loss on investment						$ 3,200,000
Number Of Companies Operated By DBOT \| company						3
Supplemental information on an unaudited pro forma basis
Revenue contributed by acquiree		$ 15,838
Net loss contributed by acquiree								$ 1,900,000
Revenue					$ 3,213,000		$ 44,612,000
Net income (loss) attributable to IDEX common shareholders					$ (15,163,000)		$ 10,582,000
Acquisition-date fair value of assets acquired and liabilities assumed
Cash				247,000		$ 247,000
Other financial assets				1,686,000		1,686,000
Financial liabilities				(4,411,000)		(4,411,000)
Noncontrolling interest				(105,000)		(105,000)
Goodwill				9,324,000		9,324,000
Net assets assumed				15,055,000		$ 15,055,000
DBOT \| Continuing Membership Agreements [Member]
Acquisitions and Divestitures
Useful Life						20 years
Acquisition-date fair value of assets acquired and liabilities assumed
Intangible asset				8,255,000		$ 8,255,000
DBOT \| Customer List [Member]
Acquisitions and Divestitures
Useful Life						3 years
Acquisition-date fair value of assets acquired and liabilities assumed
Intangible asset				$ 59,000		$ 59,000