v3.26.1

Organization and Summary of Significant Accounting Policies- Narrative (Details) - USD ($)	12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Product Information [Line Items]
Entity wide disclosure on geographic areas, revenue from external customers attributed to foreign countries, percentage	51.00%	49.00%	51.00%
Disclosure on geographic areas, long-lived assets in foreign countries	47.00%	47.00%
Guarantee obligations secured by cash deposits	$ 1,417,000	$ 789,000	$ 518,000
Billed contracts receivable	3,637,000	4,422,000
Accounts receivable, allowance for doubtful accounts	1,355,000	1,230,000
Cloud computing arrangement, unamortized implementation cost	12,784,000	8,250,000
Goodwill, impairment loss	$ 0	0	0
Standard warranty term	1 year
Research and development expense	$ 9,511,000	9,408,000	$ 9,799,000
Minimum
Product Information [Line Items]
Standard warranty term	1 year
Maximum
Product Information [Line Items]
Standard warranty term	18 months
Prepaid Expenses and Other Current Assets
Product Information [Line Items]
Cloud computing arrangement, unamortized implementation cost	$ 2,209,000	1,206,000
Other Noncurrent Assets
Product Information [Line Items]
Cloud computing arrangement, unamortized implementation cost	$ 10,575,000	$ 7,044,000

Entity Wide Disclosure On Geographic Areas Long Lived Assets In Foreign Countries, Percentage

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Amount of allowance for credit loss on accounts receivable, classified as current.

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Thermon Group Holdings, Inc. 10-K