Quarterly report pursuant to Section 13 or 15(d)

Acquisitions - Narrative (Details)

v3.10.0.1
Acquisitions - Narrative (Details)
$ in Thousands
3 Months Ended 6 Months Ended
Oct. 30, 2017
CAD ($)
Oct. 30, 2017
USD ($)
Sep. 30, 2018
USD ($)
Sep. 30, 2018
USD ($)
Business Acquisition [Line Items]        
Weighted average useful life     10 years 7 months 6 days  
Goodwill, working capital adjustment related to acquisition       $ 481
Thermon Heating Systems Inc.        
Business Acquisition [Line Items]        
Equity interests acquired 100.00% 100.00%    
Payments to acquire business $ 262,415 $ 204,596,000   204,596,000
Transaction costs     $ 4,093,000 4,093,000
Operating Segments        
Business Acquisition [Line Items]        
Goodwill, working capital adjustment related to acquisition       481,000
Operating Segments | Canada        
Business Acquisition [Line Items]        
Goodwill, working capital adjustment related to acquisition       481,000
Operating Segments | Canada | Thermon Heating Systems Inc.        
Business Acquisition [Line Items]        
Goodwill acquired       $ 85,637,000