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

Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation Expense (Details)

Stock-Based Compensation Expense (Details) (USD $)	3 Months Ended		6 Months Ended					0 Months Ended	6 Months Ended			0 Months Ended	6 Months Ended	0 Months Ended	6 Months Ended	0 Months Ended	6 Months Ended			3 Months Ended		6 Months Ended			0 Months Ended	6 Months Ended			0 Months Ended	6 Months Ended	0 Months Ended	6 Months Ended	0 Months Ended	6 Months Ended
Stock-Based Compensation Expense (Details) (USD $)	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 Stock_Option_Award_Plans	Sep. 30, 2011	Aug. 02, 2012	Jul. 28, 2010 Restricted Stock and Stock Option Plan	Jul. 28, 2010 2011 Long-term Incentive Plan	Aug. 02, 2012 Stock Options	Sep. 30, 2012 Stock Options	Sep. 30, 2012 Stock Options Minimum	Sep. 30, 2012 Stock Options Maximum	Aug. 02, 2012 Restricted Stock Awards	Sep. 30, 2012 Restricted Stock Awards	Aug. 02, 2012 Restricted Stock Units	Sep. 30, 2012 Restricted Stock Units	Aug. 02, 2012 Performance Shares	Sep. 30, 2012 Performance Shares Executive_Officers	Sep. 30, 2012 Performance Shares Minimum	Sep. 30, 2012 Performance Shares Maximum	Sep. 30, 2012 Thermon Holding Corp.	Sep. 30, 2011 Thermon Holding Corp.	Sep. 30, 2012 Thermon Holding Corp.	Sep. 30, 2011 Thermon Holding Corp.	Aug. 02, 2012 Thermon Holding Corp.	Aug. 02, 2012 Thermon Holding Corp. Stock Options	Sep. 30, 2012 Thermon Holding Corp. Stock Options	Sep. 30, 2012 Thermon Holding Corp. Stock Options Minimum	Sep. 30, 2012 Thermon Holding Corp. Stock Options Maximum	Aug. 02, 2012 Thermon Holding Corp. Restricted Stock Awards	Sep. 30, 2012 Thermon Holding Corp. Restricted Stock Awards	Aug. 02, 2012 Thermon Holding Corp. Restricted Stock Units	Sep. 30, 2012 Thermon Holding Corp. Restricted Stock Units	Aug. 02, 2012 Thermon Holding Corp. Performance Shares	Sep. 30, 2012 Thermon Holding Corp. Performance Shares Executive_Officers	Sep. 30, 2012 Thermon Holding Corp. Performance Shares Minimum	Sep. 30, 2012 Thermon Holding Corp. Performance Shares Maximum
Stock-Based Compensation Expense
Number of stock option award plans			2
Maximum number of shares of the company's common stock that may be awarded						2,767,171	2,893,341
Options outstanding (in shares)	1,581,273		1,581,273
Stock compensation expense	$ 336,000	$ 57,000	$ 394,000	$ 6,399,000																$ 336,000	$ 57,000	$ 394,000	$ 6,399,000
Stock compensation expense associated with the acceleration of the pre-IPO options				6,310,000																			6,310,000
Stock options granted in period								56,532																	56,532
Stock awards granted in period												12,546		71,923		44,146													12,546		71,923		44,146
Closing price per share					$ 21.52																			$ 21.52
Assumptions used to estimate grant date fair value of employee stock options granted
Share Price									501,000																	501,000
Estimated volatility (as a percent)									40.50%																	40.50%
Risk free rate (as a percent)									0.63%																	0.63%
Life of options									6 years 7 months 28 days																	6 years 7 months 28 days
Expected dividend									0.00																	0.00
Period in which fair value of options will be expensed on a straight line basis									5 years				1 year		3 years		3 years									5 years				1 year		3 years		3 years
Number of executives issued stock																	4																	4
Total fair value of options issued													$ 270,000		$ 1,548,000		$ 960,000													$ 270,000		$ 1,548,000		$ 960,000
Possible number of shares issued each year																		0	29,430																0	29,430
Vesting period										5 years	10 years																5 years	10 years
Expiration term											10 years																	10 years