Consolidated Statements Of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Payments to Acquire Businesses, Net of Cash Acquired	$ 150	$ 0	$ 0
OPERATING ACTIVITIES
Net income	1,043	967	1,156
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion	136	172	197
Stock-based compensation	242	196	178
Loss on Conversion of Convertible Notes	0	0	10
Change in assets and liabilities:
Receivables, net	(25)	(136)	127
Other assets	10	3	22
Accounts payable	(44)	5	13
Accrued and other liabilities	43	190	(10)
Deferred income taxes, net	204	100	(403)
Deferred net revenue (online-enabled games)	83	81	175
Net cash provided by operating activities	1,692	1,578	1,465
INVESTING ACTIVITIES
Capital expenditures	(107)	(123)	(93)
Proceeds from maturities and sales of short-term investments	3,166	1,281	941
Purchase of short-term investments	(2,287)	(1,917)	(1,332)
Net cash used in investing activities	622	(759)	(484)
FINANCING ACTIVITIES
Proceeds from issuance of senior notes, net of issuance costs	0	0	989
Payment of convertible notes	0	(163)	(470)
Proceeds from issuance of common stock	78	72	107
Payments Related to Tax Withholding for Share-based Compensation	120	130	156
Repurchase and retirement of common stock	(601)	(508)	(1,018)
Net cash used in financing activities	(643)	(729)	(548)
Effect of foreign exchange on cash and cash equivalents	22	(18)	(8)
Increase in cash and cash equivalents	1,693	72	425
Beginning cash and cash equivalents	2,565	2,493	2,068
Ending cash and cash equivalents	4,258	2,565	2,493
Supplemental cash flow information:
Cash paid during the year for income taxes, net	57	51	35
Cash paid during the year for interest	$ 42	$ 43	$ 4