Graham Corporation Quarterly report pursuant to Section 13 or 15(d)

Changes in Accumulated Other Comprehensive Loss - Reclassifications Out of Accumulated Other Comprehensive Loss by Component (Detail) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before provision for income taxes	$ 3,448	$ 3,626
Provision for income taxes	1,087	1,234
Net income	2,361	2,392
Reclassifications Out of Accumulated Other Comprehensive Loss [Member] \| Amortization of Unrecognized Prior Service Benefit [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before provision for income taxes		25
Reclassifications Out of Accumulated Other Comprehensive Loss [Member] \| Amortization of Actuarial Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before provision for income taxes	(303)	(155)
Reclassifications Out of Accumulated Other Comprehensive Loss [Member] \| Pension and Other Postretirement Benefits Items [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before provision for income taxes	(303)	(130)
Provision for income taxes	(107)	(46)
Net income	$ (196)	$ (84)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.