CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
Statement Of Income And Comprehensive Income [Abstract]
Unrealized gains(losses) on available-for-sale securities, tax	$ 0	$ (29)	$ 0	$ 43
Amortization of loss on derivative contract, tax	0	62	0	188
Change in Other Benefit Plan minimum liability, tax	$ 0	$ 0	$ 0	$ 70