Acquisitions - Purchase Price (Details) - Thermon Heating Systems Inc. $ in Thousands, $ in Thousands  | 
6 Months Ended | ||
|---|---|---|---|
| 
 Oct. 30, 2017  
CAD ($) 
 | 
 Oct. 30, 2017  
USD ($) 
 | 
 Sep. 30, 2018  
USD ($) 
 | 
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| Business Acquisition [Line Items] | |||
| Consideration to or on behalf of sellers | $ 262,415 | $ 204,596 | $ 204,596 | 
| Fair value of total consideration transferred | $ 204,596 | ||
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- Definition 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. No definition available. 
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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
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