v3.25.4
Business Acquisitions - Additional Information (Detail)
$ in Millions
 3 Months Ended 12 Months Ended
Aug. 08, 2025
USD ($)
May 02, 2025
USD ($)
Mar. 13, 2025
USD ($)
Aug. 05, 2024
USD ($)
May 07, 2024
USD ($)
Jan. 19, 2024
USD ($)
Jan. 09, 2023
USD ($)
Dec. 31, 2025
USD ($)
Sep. 30, 2025
USD ($)
Jun. 30, 2025
USD ($)
Mar. 31, 2025
USD ($)
Dec. 31, 2025
USD ($)
Acquisitions
Dec. 31, 2024
USD ($)
Acquisitions
Dec. 31, 2023
USD ($)
Acquisitions
Business Acquisition [Line Items]                            
Number of business acquired | Acquisitions                       3 4 1
Goodwill acquired                       $ 207.7 $ 19.9  
Goodwill               $ 783.6       783.6 573.8 $ 553.9
Contingent consideration on purchase price               75.1       75.1 10.7  
Working capital adjustment receivable from seller                       0.0 1.0 0.0
Business acquisition, initial cash payment                       194.9 16.2 9.5
Acquisition costs incurred                       6.2 3.4 2.6
Payment of contingent consideration liability                       3.2 0.0 3.7
Revenues                       463.4 398.8 382.8
Net (loss) income attributable to Emerald Holding, Inc.                       $ (30.7) 2.2 (8.2)
Trade Names [Member]                            
Business Acquisition [Line Items]                            
Weighted-average amortization period                       19 years    
Customer Relationship Intangibles [Member]                            
Business Acquisition [Line Items]                            
Weighted-average amortization period                       7 years    
Generis Group [Member]                            
Business Acquisition [Line Items]                            
Goodwill $ 57.4                          
Purchase price 64.6                          
Cash acquired from business acquisition 7.2                          
Measurement period adjustments in goodwill and other non-current liability               (0.3)            
Contingent consideration on purchase price 6.8                          
Intangible assets 13.3                          
Working capital adjustment receivable from seller 1.0                     $ 0.8    
Business acquisition, initial cash payment 51.6                          
Revenues                       12.4    
Net (loss) income attributable to Emerald Holding, Inc.                       3.6    
Generis Group [Member] | Selling, General and Administrative Expenses [Member]                            
Business Acquisition [Line Items]                            
Acquisition costs incurred 1.3                          
Generis Group [Member] | Trade Names [Member]                            
Business Acquisition [Line Items]                            
Intangible assets $ 6.9                          
Weighted-average amortization period 10 years                          
Assumed residual value $ 0.0                          
Generis Group [Member] | Customer Relationship Intangibles [Member]                            
Business Acquisition [Line Items]                            
Intangible assets $ 6.4                          
Weighted-average amortization period 3 years                          
Assumed residual value $ 0.0                          
Generis Group [Member] | Estimated Fair Value [Member]                            
Business Acquisition [Line Items]                            
Contingent consideration on purchase price               20.9       20.9    
This is Beyond Ltd [Member]                            
Business Acquisition [Line Items]                            
Goodwill   $ 122.1                        
Purchase price   165.5                        
Cash acquired from business acquisition   33.9                        
Intangible assets   30.1                        
Business acquisition, initial cash payment   122.1                        
Revenues                       39.9    
Net (loss) income attributable to Emerald Holding, Inc.                       11.3    
This is Beyond Ltd [Member] | Selling, General and Administrative Expenses [Member]                            
Business Acquisition [Line Items]                            
Acquisition costs incurred   2.9                        
This is Beyond Ltd [Member] | Trade Names [Member]                            
Business Acquisition [Line Items]                            
Intangible assets   $ 10.4                        
Weighted-average amortization period   10 years                        
Assumed residual value   $ 0.0                        
This is Beyond Ltd [Member] | Customer Relationship Intangibles [Member]                            
Business Acquisition [Line Items]                            
Intangible assets   $ 19.7                        
Weighted-average amortization period   5 years                        
Assumed residual value   $ 0.0                        
This is Beyond Ltd [Member] | Estimated Fair Value [Member]                            
Business Acquisition [Line Items]                            
Contingent consideration on purchase price   $ 9.5           27.2       27.2    
Insurtech Insights [Member]                            
Business Acquisition [Line Items]                            
Goodwill     $ 27.4                      
Purchase price     27.9                      
Cash acquired from business acquisition     1.0                      
Intangible assets     4.4                      
Business acquisition, initial cash payment     19.4                      
Escrow payment                   $ 2.7        
Revenues                       13.3    
Net (loss) income attributable to Emerald Holding, Inc.                       3.4    
Insurtech Insights [Member] | 2025 London Event Payment [Member]                            
Business Acquisition [Line Items]                            
Payment of contingent consideration liability                 $ 2.8          
Insurtech Insights [Member] | Selling, General and Administrative Expenses [Member]                            
Business Acquisition [Line Items]                            
Acquisition costs incurred     1.2                      
Insurtech Insights [Member] | Trade Names [Member]                            
Business Acquisition [Line Items]                            
Intangible assets     $ 2.5                      
Weighted-average amortization period     10 years                      
Assumed residual value     $ 0.0                      
Insurtech Insights [Member] | Customer Relationship Intangibles [Member]                            
Business Acquisition [Line Items]                            
Intangible assets     $ 1.9                      
Weighted-average amortization period     2 years                      
Assumed residual value     $ 0.0                      
Insurtech Insights [Member] | Estimated Fair Value [Member]                            
Business Acquisition [Line Items]                            
Contingent consideration on purchase price     $ 4.8         17.5       17.5    
Lodestone Events [Member]                            
Business Acquisition [Line Items]                            
Goodwill             $ 8.4              
Purchase price             10.2              
Business acquisition, initial cash payment             9.5              
Intangible assets             3.4              
Revenues                           9.0
Net (loss) income attributable to Emerald Holding, Inc.                           $ 4.4
Lodestone Events [Member] | Selling, General and Administrative Expenses [Member]                            
Business Acquisition [Line Items]                            
Acquisition costs incurred             0.4              
Lodestone Events [Member] | Trade Names [Member]                            
Business Acquisition [Line Items]                            
Intangible assets             $ 1.1              
Weighted-average amortization period             5 years              
Assumed residual value             $ 0.0              
Lodestone Events [Member] | Customer Relationship Intangibles [Member]                            
Business Acquisition [Line Items]                            
Intangible assets             $ 2.3              
Weighted-average amortization period             6 years              
Assumed residual value             $ 0.0              
Lodestone Events [Member] | Estimated Fair Value [Member]                            
Business Acquisition [Line Items]                            
Contingent consideration on purchase price             $ 0.7 8.4       8.4    
GRC World Forums [Member]                            
Business Acquisition [Line Items]                            
Goodwill       $ 3.7                    
Purchase price       2.9                    
Business acquisition, initial cash payment       1.2                    
Intangible assets       1.4                    
Revenues                         2.0  
Net (loss) income attributable to Emerald Holding, Inc.                         0.3  
GRC World Forums [Member] | Selling, General and Administrative Expenses [Member]                            
Business Acquisition [Line Items]                            
Acquisition costs incurred       0.4                    
GRC World Forums [Member] | Trade Names [Member]                            
Business Acquisition [Line Items]                            
Intangible assets       $ 0.4                    
Weighted-average amortization period       3 years                    
Assumed residual value       $ 0.0                    
GRC World Forums [Member] | Customer Relationship Intangibles [Member]                            
Business Acquisition [Line Items]                            
Intangible assets       $ 1.0                    
Weighted-average amortization period       3 years                    
Assumed residual value       $ 0.0                    
GRC World Forums [Member] | Estimated Fair Value [Member]                            
Business Acquisition [Line Items]                            
Contingent consideration on purchase price       1.2       $ 1.0       $ 1.0    
Glamping Americas [Member]                            
Business Acquisition [Line Items]                            
Goodwill       2.6                    
Purchase price       3.0                    
Business acquisition, initial cash payment       2.3                    
Intangible assets       0.8                    
Payment of contingent consideration liability                     $ 0.4      
Revenues                         1.2  
Net (loss) income attributable to Emerald Holding, Inc.                         0.4  
Glamping Americas [Member] | Selling, General and Administrative Expenses [Member]                            
Business Acquisition [Line Items]                            
Acquisition costs incurred       0.2                    
Glamping Americas [Member] | Trade Names [Member]                            
Business Acquisition [Line Items]                            
Intangible assets       $ 0.2                    
Weighted-average amortization period       4 years                    
Assumed residual value       $ 0.0                    
Glamping Americas [Member] | Customer Relationship Intangibles [Member]                            
Business Acquisition [Line Items]                            
Intangible assets       $ 0.6                    
Weighted-average amortization period       4 years                    
Assumed residual value       $ 0.0                    
Glamping Americas [Member] | Estimated Fair Value [Member]                            
Business Acquisition [Line Items]                            
Contingent consideration on purchase price       $ 0.4                    
The Futurist [Member]                            
Business Acquisition [Line Items]                            
Goodwill         $ 1.8                  
Purchase price         1.9                  
Business acquisition, initial cash payment         1.1                  
Revenues                         1.6  
Net (loss) income attributable to Emerald Holding, Inc.                         0.2  
The Futurist [Member] | Estimated Fair Value [Member]                            
Business Acquisition [Line Items]                            
Contingent consideration on purchase price         $ 0.9                  
Hotel Interactive [Member]                            
Business Acquisition [Line Items]                            
Goodwill           $ 11.8                
Purchase price           13.5                
Business acquisition, initial cash payment           11.6                
Business combination, post close working capital adjustment receivable           0.8                
Intangible assets           4.1                
Working capital adjustment receivable from seller                         1.0  
Revenues                         8.6  
Net (loss) income attributable to Emerald Holding, Inc.                         $ 0.5  
Hotel Interactive [Member] | Selling, General and Administrative Expenses [Member]                            
Business Acquisition [Line Items]                            
Acquisition costs incurred           0.2                
Hotel Interactive [Member] | Trade Names [Member]                            
Business Acquisition [Line Items]                            
Intangible assets           $ 1.6                
Weighted-average amortization period           10 years                
Assumed residual value           $ 0.0                
Hotel Interactive [Member] | Customer Relationship Intangibles [Member]                            
Business Acquisition [Line Items]                            
Intangible assets           $ 2.5                
Weighted-average amortization period           4 years                
Assumed residual value           $ 0.0                
Hotel Interactive [Member] | Estimated Fair Value [Member]                            
Business Acquisition [Line Items]                            
Contingent consideration on purchase price           $ 2.7