Note 10 - Comprehensive Income (Loss) - Components of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Foreign currency translation adjustment, pre-tax	$ (18,639)	$ 7,749	$ (59,070)	$ 41,196
Foreign currency translation adjustment, net of tax	(18,639)	7,749	(59,070)	41,196
Foreign currency cash flow hedges adjustment, pre-tax	(52)	(690)	196	(1,215)
Foreign currency cash flow hedges adjustment	(36)	(518)	153	(939)
Pension liability adjustment, pre-tax	(300)	321	3,279	171
Pension liability adjustment	(246)	243	2,600	130
Other comprehensive income (loss), pre-tax	(18,991)	7,380	(55,595)	40,152
Other comprehensive income (loss), net of tax	$ (18,921)	$ 7,474	$ (56,317)	$ 40,387

Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

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