v3.26.1
Cover
12 Months Ended
Mar. 31, 2026
Document Information [Line Items]  
Document Type 11-K
Amendment Flag false
Entity Registrant Name Graham Corporation
Entity Central Index Key 0000716314
EBP 001 [Member]  
Document Information [Line Items]  
Document Type 11-K
Amendment Flag false
Document Period End Date Mar. 31, 2026
Document Fiscal Year Focus 2026
Document Fiscal Period Focus FY
Entity Registrant Name Graham Corporation
Entity Central Index Key 0000716314
Current Fiscal Year End Date --03-31