Note 12 - Accumulated Other Comprehensive Income (Loss) - AOCI Change (Details) - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) Net Of Tax, Beginning of Period	$ (10,639)	$ (13,577)
Other comprehensive income (loss) before reclassifications	(2,388)	3,561
Net (gain) loss reclassified from accumulated other comprehensive income (loss)
Net current period other comprehensive income (loss)	(2,388)	3,561
Accumulated Other Comprehensive Income (Loss) Net Of Tax, End of Period	(13,027)	(10,016)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) Net Of Tax, Beginning of Period	(82)	7
Other comprehensive income (loss) before reclassifications	132	(302)
Net (gain) loss reclassified from accumulated other comprehensive income (loss)	(31)	272
Net current period other comprehensive income (loss)	101	(30)
Accumulated Other Comprehensive Income (Loss) Net Of Tax, End of Period	19	(23)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) Net Of Tax, Beginning of Period	(9,545)	(9,518)
Other comprehensive income (loss) before reclassifications
Net (gain) loss reclassified from accumulated other comprehensive income (loss)
Net current period other comprehensive income (loss)
Accumulated Other Comprehensive Income (Loss) Net Of Tax, End of Period	(9,545)	(9,518)
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) Net Of Tax, Beginning of Period	(20,266)	(23,088)
Other comprehensive income (loss) before reclassifications	(2,256)	3,259
Net (gain) loss reclassified from accumulated other comprehensive income (loss)	(31)	272
Net current period other comprehensive income (loss)	(2,287)	3,531
Accumulated Other Comprehensive Income (Loss) Net Of Tax, End of Period	(22,553)	$ (19,557)
Accumulated Other Comprehensive Income (Loss) Net Of Tax, Beginning of Period	(20,266)
Accumulated Other Comprehensive Income (Loss) Net Of Tax, End of Period	$ (22,553)