Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 294	$ 185	$ 498	$ 550
Other comprehensive income (loss), net of tax:
Net gains (losses) on available-for-sale securities	0	(3)	0	8
Net gains (losses) on derivative instruments	50	(43)	56	(80)
Foreign currency translation adjustments	(17)	9	(8)	33
Total other comprehensive income (loss), net of tax	33	(37)	48	(39)
Total comprehensive income (loss)	$ 327	$ 148	$ 546	$ 511