Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2021
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 364	$ 748	$ 653	$ 2,291
Other comprehensive income, net of tax
Net unrealized gains (losses) on available-for-sale marketable securities [net of tax benefit (provision) of $0, $1, $14 and ($1), respectively]	3	(3)	(48)	4
Reclassification adjustment for net (gains) losses on available-for-sale marketable securities included in investment and other income, net [net of tax provision of $0, $0, $0 and $0, respectively]	0	(1)	2	(1)
Other comprehensive income (loss)	3	(4)	(46)	3
Comprehensive income	$ 367	$ 744	$ 607	$ 2,294