Note 9 - Pension Plans - Net Amount Recognized (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2016	Mar. 31, 2015
Change in projected benefit obligation
Projected benefit obligation at the beginning of the year	$ 47,346	$ 44,558
Service cost	101	104	$ 108
Interest cost	1,450	1,803	1,886
Actuarial (gain) loss	(1,549)	9,036
Benefits paid	(1,830)	(1,467)
Foreign currency adjustment	(497)	(6,688)
Projected benefit obligation at year end	45,021	47,346	44,558
Change in plan assets
Fair value of plan assets at the beginning of the year	30,114	29,013
Actual return (loss) on plan assets	(156)	4,306
Employer contribution	1,009	1,089
Benefits paid from assets	(1,388)	(970)
Foreign currency adjustment	(865)	(3,324)
Plan assets at fair value at year end	28,714	30,114	29,013
Unfunded status of the plan at year end				$ 16,307	$ 17,232
Pension liability recognized on the balance sheet due after one year				16,307	17,232
Plans with projected benefit obligation and accumulated benefit obligation in excess of plan assets:
Projected benefit obligation at year end				45,021	47,346
Accumulated benefit obligation at year end				44,509	46,695
Plan assets at fair value at year end	$ 28,714	$ 30,114	$ 29,013	28,714	30,114
Amounts recognized in accumulated other comprehensive income (loss):
Unrecognized actuarial loss, before tax				(12,140)	(12,354)
Amount recognized as component of stockholders’ equity – pretax				(12,140)	(12,354)
Accumulated benefit obligation at year end				$ 44,509	$ 46,695