Thermon Group Holdings, Inc. Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Foreign Exchange Contracts by Currency (Details) (Thermon Holding Corp., Foreign Exchange Forward Contracts, USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2014
Derivatives [Line Items]
Notional amount	$ 11,130invest_DerivativeNotionalAmount	$ 8,178invest_DerivativeNotionalAmount
Russian Rubles
Derivatives [Line Items]
Notional amount	1,698	772
Euro
Derivatives [Line Items]
Notional amount	2,672	2,386
Canadian Dollars
Derivatives [Line Items]
Notional amount	356	0
South Korean Won
Derivatives [Line Items]
Notional amount	3,623	532
India, Rupees
Derivatives [Line Items]
Notional amount	0	2,574
United Kingdom, Pounds
Derivatives [Line Items]
Notional amount	0	201
Mexico, Pesos
Derivatives [Line Items]
Notional amount	803	1,077
Other
Derivatives [Line Items]
Notional amount	$ 1,978	$ 636