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

Changes in Accumulated Other Comprehensive Loss - Reclassifications Out of Accumulated Other Comprehensive Loss by Component (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before provision for income taxes									$ 8,730	$ 21,752	$ 14,710
Provision for income taxes									2,599	7,017	4,565
Net income	$ 520	$ 1,274	$ 1,976	$ 2,361	$ 4,165	$ 3,992	$ 4,186	$ 2,392	6,131	14,735	$ 10,145
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										102
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									(1,214)	(616)
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									(1,214)	(514)
Provision for income taxes									(429)	(182)
Net income									$ (785)	$ (332)

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