Related Party Transactions - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Onex Corporation [Member] \| As Converted Common Stock [Member]
Related Party Transaction [Line Items]
Related parties, ownership percentage	93.20%
Convex Group Ltd [Member] \| Onex Corporation [Member]
Related Party Transaction [Line Items]
Related parties, ownership percentage	93.00%
Convex Group Ltd [Member] \| Cost Of Revenues [Member]
Related Party Transaction [Line Items]
Selling, general and administrative expense insurance	$ 0	$ 0

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Emerald Holding, Inc. 10-Q