(Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Changes in accumulated other comprehensive (loss) income
Balance	$ (37,896)	$ (30,624)
Other comprehensive income (loss) before reclassifications	(9,255)	(7,291)
Amounts reclassified from accumulated other comprehensive income (loss)	9	19
Balance	(47,142)	(37,896)
Foreign currency translation adjustments
Changes in accumulated other comprehensive (loss) income
Balance	(38,580)	(31,216)
Other comprehensive income (loss) before reclassifications	(9,086)	(7,364)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Balance	(47,666)	(38,580)
Unrealized gain (loss) on derivative instruments
Changes in accumulated other comprehensive (loss) income
Balance	600	617
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	0	(17)
Balance	600	600
Unrealized gain (loss) on available- for-sales securities
Changes in accumulated other comprehensive (loss) income
Balance	84	(25)
Other comprehensive income (loss) before reclassifications	(169)	73
Amounts reclassified from accumulated other comprehensive income (loss)	9	36
Balance	$ (76)	$ 84