Graham Corporation Annual report pursuant to Section 13 and 15(d)

Annual report pursuant to Section 13 and 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- The Company and Its Accounting Policies (Policies)
Notes Tables
Notes Details

Segment Information - Additional Information (Detail)

v3.8.0.1

Segment Information - Additional Information (Detail) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2018 USD ($) Customer	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($) Customer	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2018 USD ($) Segment Customer	Mar. 31, 2017 USD ($) Customer	Mar. 31, 2016 USD ($) Customer
Segment Reporting Information [Line Items]
Number of reportable operating segments \| Segment									1
Net sales	$ 22,178	$ 17,281	$ 17,224	$ 20,851	$ 25,624	$ 22,654	$ 21,126	$ 22,365	$ 77,534	$ 91,769	$ 90,039
Customer Concentration Risk [Member] \| Net Sales [Member]
Segment Reporting Information [Line Items]
Number of customers \| Customer	0				1				0	1	0
Concentration risk percentage										11.00%
Customer Concentration Risk [Member] \| Net Sales [Member] \| Minimum [Member]
Segment Reporting Information [Line Items]
Concentration risk percentage									10.00%		10.00%
SUDAN [Member]
Segment Reporting Information [Line Items]
Net sales									$ 0	$ 0	$ 0
IRAN [Member]
Segment Reporting Information [Line Items]
Net sales									0	0	0
SYRIA [Member]
Segment Reporting Information [Line Items]
Net sales									$ 0	$ 0	$ 0

- Definition

The number of customers with sales amounting to 10% or greater of total consolidated sales.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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