Acquisitions and Divestitures - Pro Forma Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Business Combination and Asset Acquisition [Abstract]
Total revenue	$ 27,047	$ 32,418	$ 91,369	$ 75,747
Net loss attributable to IDEX common shareholders	$ (50,854)	$ (6,132)	$ (66,325)	$ (42,398)
Earnings (loss) per share
Basic (in dollars per share)	$ (0.11)	$ (0.02)	$ (0.15)	$ (0.20)
Diluted (in dollars per share)	$ (0.11)	$ (0.02)	$ (0.15)	$ (0.20)
Weighted average shares outstanding
Basic (in shares)	477,214,431	256,752,912	440,151,607	211,193,769
Diluted (in shares)	477,214,431	256,752,912	440,151,607	211,193,769

Weighted Average Number Of Shares Outstanding, Pro Forma

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Pro forma basic earnings per share or earnings per unit, which is commonly presented in initial public offerings based on the terms of the offering.

+ References

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-Publisher FASB
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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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Pro forma diluted earnings per share, which is commonly presented in initial public offerings.

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The weighted average number of shares or units and dilutive common stock or unit equivalents outstanding in the calculation of proforma diluted earnings per share (earnings per unit), which is commonly presented in initial public offerings based on the terms of the offering.

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The weighted average number of shares (units) outstanding in the calculation of pro forma basic earnings per share (earnings per unit), which is commonly presented in initial public offerings based on the terms of the offering.

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