Annual report pursuant to Section 13 and 15(d)

Organization and Summary of Significant Accounting Policies (Details)

v3.7.0.1
Organization and Summary of Significant Accounting Policies (Details)
 3 Months Ended 12 Months Ended
Apr. 30, 2010
USD ($)
Mar. 31, 2017
USD ($)
Dec. 31, 2016
USD ($)
Sep. 30, 2016
USD ($)
Jun. 30, 2016
USD ($)
Mar. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Sep. 30, 2015
USD ($)
Jun. 30, 2015
USD ($)
Mar. 31, 2017
USD ($)
Mar. 31, 2016
USD ($)
Mar. 31, 2015
USD ($)
Business Acquisition [Line Items]                        
Increase (Decrease) in Accounts Receivable                   $ (5,212,000) $ 5,211,000 $ (12,242,000)
Selling, General and Administrative Expense                   77,715,000 80,729,000 76,868,000
Goodwill impaired                   0 (1,240,000) 0
Asset Impairment Charges                     473,000  
Cost of selling controlling interest $ 129,252,000                      
Sales                   264,130,000 281,928,000 308,578,000
Gross Profit   $ 28,274,000 $ 28,619,000 $ 28,924,000 $ 26,114,000 $ 32,095,000 $ 35,129,000 $ 33,354,000 $ 30,737,000 111,931,000 131,315,000 154,704,000
Net cash provided by (used in) operations                   26,440,000 47,920,000 51,731,000
Non-U.S.                   $ 21,698,000 $ 19,304,000 $ 40,069,000
Disclosure on Geographic Areas, Long-Lived Assets in Foreign Countries   59.00%       58.00%       59.00% 58.00%  
Entity Wide Disclosure On Geographic Areas, Revenue From External Customers Attributed To Foreign Countries, Percentage                   55.00% 55.00% 63.00%
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Amortization of Deferred Charges                   $ 391,000 $ 732,000 $ 464,000
Research and Development Expense                   3,501,000 3,338,000 2,907,000
Debt issuance costs, net   $ 524,000       $ 888,000       $ 524,000 888,000  
Group of investors and other private equity firms [Member]                        
Business Acquisition [Line Items]                        
Number of other private equity firms 2                      
Land Improvements [Member] | Minimum [Member]                        
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Property, Plant and Equipment, Estimated Useful Lives                   15 years    
Land Improvements [Member] | Maximum [Member]                        
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Property, Plant and Equipment, Estimated Useful Lives                   20 years    
Building and Building Improvements [Member] | Minimum [Member]                        
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Property, Plant and Equipment, Estimated Useful Lives                   10 years    
Building and Building Improvements [Member] | Maximum [Member]                        
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Property, Plant and Equipment, Estimated Useful Lives                   40 years    
Machinery and equipment [Member] | Minimum [Member]                        
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Property, Plant and Equipment, Estimated Useful Lives                   3 years    
Machinery and equipment [Member] | Maximum [Member]                        
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Property, Plant and Equipment, Estimated Useful Lives                   25 years    
Furniture and Fixtures [Member] | Minimum [Member]                        
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Property, Plant and Equipment, Estimated Useful Lives                   3 years    
Furniture and Fixtures [Member] | Maximum [Member]                        
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Property, Plant and Equipment, Estimated Useful Lives                   10 years    
Software Development [Member] | Minimum [Member]                        
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Property, Plant and Equipment, Estimated Useful Lives                   5 years    
Software Development [Member] | Maximum [Member]                        
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Property, Plant and Equipment, Estimated Useful Lives                   7 years    
Allowance for Doubtful Accounts [Member]                        
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Balance, beginning of period         656,000       785,000 $ 656,000 785,000 751,000
Reductions to expense                   307,000    
Additions charged to expense                     214,000 175,000
Write-off of uncollectible accounts                   (445,000) (343,000) (141,000)
Balance, end of period   518,000       656,000       518,000 656,000 785,000
Inventory Valuation Reserve [Member]                        
Movement in Valuation Allowances and Reserves [Roll Forward]                        
Balance, beginning of period         $ 1,287,000       $ 1,116,000 1,287,000 1,116,000 893,000
Reductions to expense                   306,000 212,000 56,000
Additions charged to expense                   348,000 383,000 279,000
Balance, end of period   $ 1,329,000       $ 1,287,000       $ 1,329,000 1,287,000 $ 1,116,000
Predecessor [Member] | Group of investors and other private equity firms [Member] | Thermon Holding Corp. [Member]                        
Business Acquisition [Line Items]                        
Fair value of total consideration transferred $ 321,500,000                      
Consideration transferred, liabilities incurred $ 210,000,000                      
Correction of Marketing, General and Administrative and Engineering Expense                        
Business Acquisition [Line Items]                        
Selling, General and Administrative Expense                     498,000  
Accounting Standards Update 2015-07 [Member]                        
Business Acquisition [Line Items]                        
Increase (Decrease) in Accounts Receivable                     (1,061,000)  
Increase (Decrease) in Other Noncurrent Assets                     $ 1,061,000  
Customer Concentration Risk                        
Business Acquisition [Line Items]                        
Concentration risk, percentage                   14.00% 2.00%