v3.26.1
Acquisitions - Additional Information (Detail)
$ / shares in Units, € in Millions
 1 Months Ended 3 Months Ended 6 Months Ended
Jun. 01, 2026
USD ($)
$ / shares
shares
Feb. 13, 2026
USD ($)
Jan. 03, 2025
USD ($)
Jun. 30, 2026
USD ($)
Jun. 30, 2026
USD ($)
Mar. 31, 2026
USD ($)
Jun. 30, 2025
USD ($)
Mar. 31, 2025
USD ($)
Jun. 30, 2026
USD ($)
Jun. 30, 2026
EUR (€)
Jun. 30, 2025
USD ($)
May 29, 2026
$ / shares
Business Acquisition Contingent Consideration [Line Items]                        
Repayment of Thermon indebtedness $ 141,682,000                      
Acquisition and integration expense         $ 45,461,000   $ 32,000   $ 55,742,000   $ 8,175,000  
Net (loss) income         (34,489,000) $ (248,000) 10,106,000 $ 36,442,000 (34,736,000)   46,549,000  
Net income attributable to CECO Environmental Corp.         (34,768,000)   $ 9,510,000   (35,166,000)   $ 45,494,000  
Revenues | €                   € 750    
Land, Building and Improvements                        
Business Acquisition Contingent Consideration [Line Items]                        
Property and equipment       $ 14,700,000 14,700,000       14,700,000      
Vehicles                        
Business Acquisition Contingent Consideration [Line Items]                        
Property and equipment       2,100,000 2,100,000       2,100,000      
Other Machinery and Equipment                        
Business Acquisition Contingent Consideration [Line Items]                        
Property and equipment       600,000 600,000       600,000      
Thermon Group Holdings, Inc.                        
Business Acquisition Contingent Consideration [Line Items]                        
Consideration received per share | $ / shares $ 79.03                     $ 61.14
Consideration Received (Per Share) | $ / shares $ 63.89                      
Shares Converted | shares 0.811                      
Share value of cash and stock consideration $ 64                      
Acquisition of equity                       4.70%
Fair values of the assets acquired and liabilities assumed and allocated to goodwill 1,210,500,000                      
Acquisition Related Costs         22,600,000       34,300,000      
Acquisition and integration expense                 8,900,000      
Fair value       9,500,000                
Property and equipment $ 129,785,000                      
Net (loss) income       (3,600,000)                
Net income attributable to CECO Environmental Corp.       (5,300,000)                
Revenues       49,600,000                
Transaction costs                 34,300,000      
Thermon Group Holdings, Inc. | Technology                        
Business Acquisition Contingent Consideration [Line Items]                        
Intangible assets, Useful Life 20 years                      
Thermon Group Holdings, Inc. | Customer lists | Minimum                        
Business Acquisition Contingent Consideration [Line Items]                        
Intangible assets, Useful Life 20 years                      
Thermon Group Holdings, Inc. | Customer lists | Maximum                        
Business Acquisition Contingent Consideration [Line Items]                        
Intangible assets, Useful Life 25 years                      
Thermon Group Holdings, Inc. | Tradenames                        
Business Acquisition Contingent Consideration [Line Items]                        
Intangible assets, Useful Life 20 years                      
Thermon Group Holdings, Inc. | Backlog                        
Business Acquisition Contingent Consideration [Line Items]                        
Intangible assets, Useful Life 3 years                      
Thermon Group Holdings, Inc. | Common Stock                        
Business Acquisition Contingent Consideration [Line Items]                        
Consideration received per share | $ / shares $ 10                      
Consideration Received (Per Share) | $ / shares $ 0.684                      
Flexible Specialty Products LLC                        
Business Acquisition Contingent Consideration [Line Items]                        
Cash Acquired from Acquisition   $ 6,800,000                    
Earn out, Fair value   3,300,000                    
Earnout Payments   4,000,000                    
Acquired intangible assets   $ 6,100,000                    
Intangible assets, Useful Life   10 years                    
Net assets acquired   $ 10,050,000                    
Net income attributable to CECO Environmental Corp.         500,000       700,000      
Revenues         1,400,000       1,800,000      
Profire Energy Inc                        
Business Acquisition Contingent Consideration [Line Items]                        
Repayment of Thermon indebtedness     $ 122,700,000                  
Acquisition and integration expense     2,300,000                  
Deferred cash consideration     4,600,000                  
Property and equipment     17,416,000                  
Net assets acquired     $ 120,382,000                  
Profire Energy Inc | Technology                        
Business Acquisition Contingent Consideration [Line Items]                        
Acquired intangible assets       $ 3,600,000 $ 3,600,000       $ 3,600,000      
Intangible assets, Useful Life       7 years 7 years       7 years      
Profire Energy Inc | Customer lists                        
Business Acquisition Contingent Consideration [Line Items]                        
Acquired intangible assets       $ 34,500,000 $ 34,500,000       $ 34,500,000      
Intangible assets, Useful Life       10 years 10 years       10 years      
Profire Energy Inc | Tradenames                        
Business Acquisition Contingent Consideration [Line Items]                        
Acquired intangible assets       $ 3,700,000 $ 3,700,000       $ 3,700,000      
Intangible assets, Useful Life       10 years 10 years       10 years