Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Net income (loss)	$ (186)	$ (1)	$ 436	$ 401
Other comprehensive income (loss), net of tax:
Net gains (losses) on available-for-sale securities	(4)	(5)	(4)	(5)
Net gains (losses) on derivative instruments	(6)	31	(96)	48
Foreign currency translation adjustments	(12)	(17)	24	(28)
Total other comprehensive income (loss), net of tax	(22)	9	(76)	15
Total comprehensive income (loss)	$ (208)	$ 8	$ 360	$ 416