Financing Arrangement (Tables)

9 Months Ended

Dec. 31, 2020

Debt Instruments [Abstract]

Schedule of Carrying Values Of Liability and Equity Components of Senior Notes [Table Text Block]

The carrying and fair values of the Senior Notes are as follows (in millions):

	As of December 31, 2020		As of March 31, 2020
Senior Notes:
3.70% Senior Notes due 2021	$	600	$	600
4.80% Senior Notes due 2026	400		400
Total principal amount	$	1,000	$	1,000
Unaccreted discount	(1)		(1)
Unamortized debt issuance costs	(2)		(3)
Net carrying value of Senior Notes	$	997	$	996
Fair value of Senior Notes (Level 2)	$	1,078	$	1,030

Schedule Of Interest Expense

The following table summarizes our interest expense recognized for the three and nine months ended December 31, 2020 and 2019 that is included in interest and other income (expense), net on our Condensed Consolidated Statements of Operations (in millions):

	Three Months Ended December 31,				Nine Months Ended December 31,
	2020		2019		2020		2019
Amortization of debt issuance costs	$	(1)	$	—	$	(2)	$	(1)
Coupon interest expense	(10)		(10)		(31)		(31)
Total interest expense	$	(11)	$	(10)	$	(33)	$	(32)