Note 10 - Pension Plans - Information on Plan Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Mar. 31, 2016
Fair Value, Inputs, Level 1 [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan, Fair Value of Plan Assets	$ 17	$ 121
Fair Value, Inputs, Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	398	351
Fair Value, Inputs, Level 1 [Member] | Fixed Income Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	1,326	1,225
Fair Value, Inputs, Level 1 [Member] | Mutual Fund [Member]
Defined Benefit Plan, Fair Value of Plan Assets	13,156	13,527
Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan, Fair Value of Plan Assets	14,897	15,224
Fair Value, Inputs, Level 2 [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 2 [Member] | Fixed Income Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	94	96
Fair Value, Inputs, Level 2 [Member] | Mutual Fund [Member]
Defined Benefit Plan, Fair Value of Plan Assets	13,203	13,394
Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan, Fair Value of Plan Assets	13,297	13,490
Cash and Cash Equivalents [Member]
Defined Benefit Plan, Fair Value of Plan Assets	17	121
Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	398	351
Fixed Income Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	1,420	1,321
Mutual Fund [Member]
Defined Benefit Plan, Fair Value of Plan Assets	26,359	26,921
Defined Benefit Plan, Fair Value of Plan Assets	$ 28,194	$ 28,714