Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Net income (loss)	$ (38)	$ (140)	$ 402	$ 302
Other comprehensive income (loss), net of tax:
Change in unrealized net gains and losses on available-for-sale securities	(1)	2	1	1
Reclassification adjustment for net realized gains and losses on available-for-sale securities	(1)	(1)	(1)	(1)
Change in unrealized net gains and losses on derivative instruments	(1)	5	27	(8)
Reclassification adjustment for net realized gains and losses on derivative instruments	(4)	(4)	(10)	(7)
Foreign currency translation adjustments	(6)	(32)	(11)	(31)
Total other comprehensive income (loss), net of tax	(13)	(30)	6	(46)
Total comprehensive income (loss)	$ (51)	$ (170)	$ 408	$ 256