    <SEC-DOCUMENT>0001564590-20-049098-index.html : 20201030
    <SEC-HEADER>0001564590-20-049098.hdr.sgml : 20201030
    <ACCEPTANCE-DATETIME>20201030073104
    ACCESSION NUMBER:		0001564590-20-049098
    CONFORMED SUBMISSION TYPE:	10-Q
    PUBLIC DOCUMENT COUNT:		68
    CONFORMED PERIOD OF REPORT:	20200930
    FILED AS OF DATE:		20201030
    DATE AS OF CHANGE:		20201030

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			GRAHAM CORP
    		CENTRAL INDEX KEY:			0000716314
    		STANDARD INDUSTRIAL CLASSIFICATION:	GENERAL INDUSTRIAL MACHINERY & EQUIPMENT [3560]
    		IRS NUMBER:				161194720
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			0331

    	FILING VALUES:
    		FORM TYPE:		10-Q
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-08462
    		FILM NUMBER:		201274750

    	BUSINESS ADDRESS:
    		STREET 1:		20 FLORENCE AVE
    		CITY:			BATAVIA
    		STATE:			NY
    		ZIP:			14020
    		BUSINESS PHONE:		5853432216

    	MAIL ADDRESS:
    		STREET 1:		20 FLORENCE AVENUE
    		CITY:			BATAVIA
    		STATE:			NY
    		ZIP:			14020
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>10-Q
    <SEQUENCE>1
    <FILENAME>ghm-10q_20200930.htm
    <DESCRIPTION>10-Q
    <TEXT>
    Document 1 - file: ghm-10q_20200930.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-10.1
    <SEQUENCE>2
    <FILENAME>ghm-ex101_6.htm
    <DESCRIPTION>EX-10.1
    <TEXT>
    Document 2 - file: ghm-ex101_6.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-10.2
    <SEQUENCE>3
    <FILENAME>ghm-ex102_7.htm
    <DESCRIPTION>EX-10.2
    <TEXT>
    Document 3 - file: ghm-ex102_7.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-10.4
    <SEQUENCE>4
    <FILENAME>ghm-ex104_8.htm
    <DESCRIPTION>EX-10.4
    <TEXT>
    Document 4 - file: ghm-ex104_8.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-31.1
    <SEQUENCE>5
    <FILENAME>ghm-ex311_9.htm
    <DESCRIPTION>EX-31.1
    <TEXT>
    Document 5 - file: ghm-ex311_9.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-31.2
    <SEQUENCE>6
    <FILENAME>ghm-ex312_11.htm
    <DESCRIPTION>EX-31.2
    <TEXT>
    Document 6 - file: ghm-ex312_11.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-32.1
    <SEQUENCE>7
    <FILENAME>ghm-ex321_10.htm
    <DESCRIPTION>EX-32.1
    <TEXT>
    Document 7 - file: ghm-ex321_10.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>8
    <FILENAME>gi2g5j5biqqh000001.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 8 - file: gi2g5j5biqqh000001.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>9
    <FILENAME>gdcx2mwyestn000001.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 9 - file: gdcx2mwyestn000001.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>10
    <FILENAME>gbmlwvmstpz5000001.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 10 - file: gbmlwvmstpz5000001.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.SCH
    <SEQUENCE>11
    <FILENAME>ghm-20200930.xsd
    <DESCRIPTION>XBRL TAXONOMY EXTENSION SCHEMA
    <TEXT>
    Document 11 - file: ghm-20200930.xsd

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.CAL
    <SEQUENCE>12
    <FILENAME>ghm-20200930_cal.xml
    <DESCRIPTION>XBRL TAXONOMY EXTENSION CALCULATION LINKBASE
    <TEXT>
    Document 12 - file: ghm-20200930_cal.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.DEF
    <SEQUENCE>13
    <FILENAME>ghm-20200930_def.xml
    <DESCRIPTION>XBRL TAXONOMY EXTENSION DEFINITION LINKBASE
    <TEXT>
    Document 13 - file: ghm-20200930_def.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.LAB
    <SEQUENCE>14
    <FILENAME>ghm-20200930_lab.xml
    <DESCRIPTION>XBRL TAXONOMY EXTENSION LABEL LINKBASE
    <TEXT>
    Document 14 - file: ghm-20200930_lab.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.PRE
    <SEQUENCE>15
    <FILENAME>ghm-20200930_pre.xml
    <DESCRIPTION>XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE
    <TEXT>
    Document 15 - file: ghm-20200930_pre.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>16
    <FILENAME>ghm-10q_20200930_htm.xml
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 16 - file: ghm-10q_20200930_htm.html

    Document 16 - RAW XML: ghm-10q_20200930_htm.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>17
    <FILENAME>R1.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 17 - file: R1.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>18
    <FILENAME>R2.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 18 - file: R2.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>19
    <FILENAME>R3.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 19 - file: R3.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>20
    <FILENAME>R4.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 20 - file: R4.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>21
    <FILENAME>R5.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 21 - file: R5.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>22
    <FILENAME>R6.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 22 - file: R6.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>23
    <FILENAME>R7.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 23 - file: R7.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>24
    <FILENAME>R8.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 24 - file: R8.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>25
    <FILENAME>R9.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 25 - file: R9.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>26
    <FILENAME>R10.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 26 - file: R10.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>27
    <FILENAME>R11.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 27 - file: R11.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>28
    <FILENAME>R12.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 28 - file: R12.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>29
    <FILENAME>R13.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 29 - file: R13.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>30
    <FILENAME>R14.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 30 - file: R14.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>31
    <FILENAME>R15.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 31 - file: R15.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>32
    <FILENAME>R16.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 32 - file: R16.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>33
    <FILENAME>R17.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 33 - file: R17.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>34
    <FILENAME>R18.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 34 - file: R18.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>35
    <FILENAME>R19.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 35 - file: R19.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>36
    <FILENAME>R20.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 36 - file: R20.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>37
    <FILENAME>R21.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 37 - file: R21.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>38
    <FILENAME>R22.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 38 - file: R22.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>39
    <FILENAME>R23.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 39 - file: R23.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>40
    <FILENAME>R24.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 40 - file: R24.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>41
    <FILENAME>R25.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 41 - file: R25.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>42
    <FILENAME>R26.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 42 - file: R26.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>43
    <FILENAME>R27.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 43 - file: R27.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>44
    <FILENAME>R28.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 44 - file: R28.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>45
    <FILENAME>R29.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 45 - file: R29.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>46
    <FILENAME>R30.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 46 - file: R30.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>47
    <FILENAME>R31.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 47 - file: R31.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>48
    <FILENAME>R32.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 48 - file: R32.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>49
    <FILENAME>R33.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 49 - file: R33.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>50
    <FILENAME>R34.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 50 - file: R34.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>51
    <FILENAME>R35.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 51 - file: R35.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>52
    <FILENAME>R36.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 52 - file: R36.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>53
    <FILENAME>R37.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 53 - file: R37.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>54
    <FILENAME>R38.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 54 - file: R38.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>55
    <FILENAME>R39.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 55 - file: R39.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>56
    <FILENAME>R40.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 56 - file: R40.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>57
    <FILENAME>R41.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 57 - file: R41.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>58
    <FILENAME>R42.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 58 - file: R42.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>59
    <FILENAME>R43.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 59 - file: R43.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>60
    <FILENAME>R44.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 60 - file: R44.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>61
    <FILENAME>R45.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 61 - file: R45.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>62
    <FILENAME>R46.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 62 - file: R46.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EXCEL
    <SEQUENCE>63
    <FILENAME>Financial_Report.xlsx
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 63 - file: Financial_Report.xlsx

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>64
    <FILENAME>Show.js
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 64 - file: Show.js

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>65
    <FILENAME>report.css
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 65 - file: report.css

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>66
    <FILENAME>FilingSummary.xml
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 66 - file: FilingSummary.html

    Document 66 - RAW XML: FilingSummary.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>JSON
    <SEQUENCE>69
    <FILENAME>MetaLinks.json
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 69 - file: MetaLinks.json

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>ZIP
    <SEQUENCE>70
    <FILENAME>0001564590-20-049098-xbrl.zip
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 70 - file: 0001564590-20-049098-xbrl.zip

    </DOCUMENT>
    </SEC-DOCUMENT>