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

Segment Information - Breakdown of Net Sales by Geographic Area (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Segment Reporting Information [Line Items]
Net sales	$ 25,624	$ 22,654	$ 21,126	$ 22,365	$ 22,301	$ 17,323	$ 22,798	$ 27,617	$ 91,769	$ 90,039	$ 135,169
Africa [Member]
Segment Reporting Information [Line Items]
Net sales									150	112	237
Asia [Member]
Segment Reporting Information [Line Items]
Net sales									7,711	8,859	11,253
Australia & New Zealand [Member]
Segment Reporting Information [Line Items]
Net sales									42	230	330
Canada [Member]
Segment Reporting Information [Line Items]
Net sales									3,506	8,702	15,807
Central America [Member]
Segment Reporting Information [Line Items]
Net sales									38	36	1,772
Europe [Member]
Segment Reporting Information [Line Items]
Net sales									533	856	943
Mexico [Member]
Segment Reporting Information [Line Items]
Net sales									2,690	620	407
Middle East [Member]
Segment Reporting Information [Line Items]
Net sales									3,160	11,039	10,155
South America [Member]
Segment Reporting Information [Line Items]
Net sales									4,773	2,558	7,866
U.S. [Member]
Segment Reporting Information [Line Items]
Net sales									$ 69,166	$ 57,027	$ 86,399