Consolidated Statement of Stockholders Equity (USD $) In Thousands, unless otherwise specified	Total	Directors	Common Stock ($.01 par value)	Additional Paid-in Capital	Additional Paid-in Capital Directors	Retained Earnings	ESOP Debt Guarantee	Accumulated Other Comprehensive Loss
Opening Balance at Mar. 31, 2012	$ 160,466		$ 193	$ 189,260		$ 25,895	$ (975)	$ (53,907)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	78,296					78,296
Change in foreign currency translation adjustment	(2,183)							(2,183)
Change in net unrealized gain on investments, net of tax	228							228
Change in derivatives qualifying as hedges, net of tax	(388)							(388)
Change in pension liability and postretirement obligations, net of tax	95							95
Stock compensation - directors	2,973	361		2,973	361
Stock Issued During Period, Value, Stock Options Exercised	295		2	293
Earned ESOP shares	420			(3)			423
closing balance at Mar. 31, 2013	239,987		195	192,308		104,191	(552)	(56,155)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	30,421					30,421
Dividends declared	(792)					(792)
Change in foreign currency translation adjustment	3,067							3,067
Change in net unrealized gain on investments, net of tax	(1,040)							(1,040)
Change in derivatives qualifying as hedges, net of tax	254							254
Change in pension liability and postretirement obligations, net of tax	12,738							12,738
Stock compensation - directors	3,318	315		3,318	315
Stock Issued During Period, Value, Stock Options Exercised	2,194		2	2,192
Tax effect of exercise of stock options	613			613
Earned ESOP shares	605			195			410
Restricted stock units released, 56,203 shares, net of shares withheld for minimum statutory tax obligation			1	(395)
closing balance at Mar. 31, 2014	291,286		198	198,546		133,820	(142)	(41,136)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	27,190					27,190
Dividends declared	(3,199)					(3,199)
Change in foreign currency translation adjustment	(29,907)							(29,907)
Change in net unrealized gain on investments, net of tax	(909)							(909)
Change in derivatives qualifying as hedges, net of tax	(334)							(334)
Change in pension liability and postretirement obligations, net of tax	(20,162)							(20,162)
Stock compensation - directors	3,455	440		3,455	440
Stock Issued During Period, Value, Stock Options Exercised	1,607		2	1,605
Tax effect of exercise of stock options	(65)			(65)
Earned ESOP shares	251			109			142
Restricted stock units released, 56,203 shares, net of shares withheld for minimum statutory tax obligation	(934)		0	(934)		0	0	0
closing balance at Mar. 31, 2015	$ 268,719		$ 200	$ 203,156		$ 157,811	$ 0	$ (92,448)