Annual report pursuant to Section 13 and 15(d)

Document and Entity Information

v3.20.1
Document and Entity Information - USD ($)
 12 Months Ended
Mar. 31, 2020
Jun. 01, 2020
Sep. 30, 2019
Cover [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Mar. 31, 2020    
Document Fiscal Year Focus 2020    
Document Fiscal Period Focus FY    
Trading Symbol GHM    
Entity Registrant Name GRAHAM CORP    
Entity Central Index Key 0000716314    
Current Fiscal Year End Date --03-31    
Entity Well-known Seasoned Issuer No    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Filer Category Non-accelerated Filer    
Entity Shell Company false    
Entity Emerging Growth Company false    
Entity Small Business true    
Title of 12(b) Security Common Stock, Par Value $0.10 Per Share    
Security Exchange Name NYSE    
Entity File Number 1-8462    
Entity Tax Identification Number 16-1194720    
Entity Incorporation, State or Country Code DE    
Entity Address, Address Line One 20 Florence Avenue    
Entity Address, City or Town Batavia    
Entity Address, State or Province NY    
Entity Address, Postal Zip Code 14020    
City Area Code 585    
Local Phone Number 343-2216    
Entity Interactive Data Current Yes    
Document Annual Report true    
Document Transition Report false    
Entity Common Stock, Shares Outstanding   9,855,963  
Entity Public Float     $ 189,547,236
Documents Incorporated by Reference

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the Registrant's definitive Proxy Statement, to be filed in connection with the Registrant's 2020 Annual Meeting of Stockholders to be held on August 11, 2020, are incorporated by reference into Part III, Items 10, 11, 12, 13 and 14 of this filing.