Thermon Group Holdings, Inc. Annual report pursuant to Section 13 and 15(d)

Related-Party Transactions (Details) (USD $)	9 Months Ended	12 Months Ended
Related-Party Transactions (Details) (USD $)	Dec. 31, 2014	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Related Party Transaction [Line Items]
Non-cash Reduction of Related Party Liability	$ 617,000
Payments to settle the CHS transactions		3,890,000	2,055,000	289,000
Professional Fees Withheld to Settle Related Party Transactions	42,000
Amounts Determined not to be Payable to Predecessor Owners	575,000
CHS Transactions [Member]
Related Party Transaction [Line Items]
Potential expenses from indemnity fund		3,589,000
Consideration received to settle the CHS Transactions		1,700,000
Settlement payments received from related parties		1,133,000
Non-cash Reduction of Related Party Liability		567,000
Gain on settlement of related party transactions		$ 931,000	$ 0	$ 0