CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net income (loss)	$ 99,806	$ (21,184)	$ 178,385	$ 57,526
Unrealized holding gain (losses), net of tax effect of ($11), ($61), ($497) and $36, respectively	1,928	2,615	(8,070)	2,618
Reclassification of realized transactions, net of tax effect of $776, $0, $776 and $51, respectively	(1,340)	(29)	(1,390)	(170)
Change in net foreign currency translation adjustment	0	1,140	0	1,140
Other comprehensive income (loss), net of taxes	588	3,726	(9,460)	3,588
Total comprehensive income (loss)	$ 100,394	$ (17,458)	$ 168,925	$ 61,114