Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 357	$ 392
Other comprehensive income, net of tax
Net unrealized losses on available-for-sale debt securities [net of tax benefit of $1 and $2, respectively]	(5)	(8)
Reclassification of net losses realized on available-for-sale debt securities included in investment and other income, net [net of tax provision of $0 and $0, respectively]	3	0
Other comprehensive loss	(2)	(8)
Comprehensive income	$ 355	$ 384