Financial Instruments - Investments by Category and Related Balance Sheet Classification (Details) - USD ($) $ in Millions	Oct. 30, 2020	Apr. 24, 2020
Available-for-sale securities:
Cost	$ 6,870	$ 6,847
Unrealized Gains	196	135
Unrealized Losses	(59)	(141)
Fair Value	7,007	6,841
Held-to-maturity securities:
Fair Value	886
Total debt securities
Cost	7,756
Unrealized Gains	196
Unrealized Losses	(59)
Fair Value	7,893
Investments
Available-for-sale securities:
Fair Value	6,971	6,808
Total debt securities
Fair Value	7,857
Other Assets
Available-for-sale securities:
Fair Value	36	33
Total debt securities
Fair Value	36
Level 2
Available-for-sale securities:
Cost	6,337	6,269
Unrealized Gains	157	88
Unrealized Losses	(59)	(138)
Fair Value	6,435	6,219
Level 2 \| Investments
Available-for-sale securities:
Fair Value	6,435	6,219
Level 2 \| Other Assets
Available-for-sale securities:
Fair Value	0	0
Corporate debt securities \| Level 2
Available-for-sale securities:
Cost	4,234	4,285
Unrealized Gains	124	66
Unrealized Losses	(32)	(90)
Fair Value	4,326	4,261
Corporate debt securities \| Level 2 \| Investments
Available-for-sale securities:
Fair Value	4,326	4,261
Corporate debt securities \| Level 2 \| Other Assets
Available-for-sale securities:
Fair Value	0	0
U.S. government and agency securities \| Level 1
Available-for-sale securities:
Cost	497	542
Unrealized Gains	39	47
Unrealized Losses	0	0
Fair Value	536	589
U.S. government and agency securities \| Level 1 \| Investments
Available-for-sale securities:
Fair Value	536	589
U.S. government and agency securities \| Level 1 \| Other Assets
Available-for-sale securities:
Fair Value	0	0
U.S. government and agency securities \| Level 2
Available-for-sale securities:
Cost	888	746
Unrealized Gains	1	1
Unrealized Losses	(1)	0
Fair Value	888	747
U.S. government and agency securities \| Level 2 \| Investments
Available-for-sale securities:
Fair Value	888	747
U.S. government and agency securities \| Level 2 \| Other Assets
Available-for-sale securities:
Fair Value	0	0
Mortgage-backed securities \| Level 2
Available-for-sale securities:
Cost	661	705
Unrealized Gains	27	20
Unrealized Losses	(19)	(28)
Fair Value	669	697
Mortgage-backed securities \| Level 2 \| Investments
Available-for-sale securities:
Fair Value	669	697
Mortgage-backed securities \| Level 2 \| Other Assets
Available-for-sale securities:
Fair Value	0	0
Non-U.S. government and agency securities \| Level 2
Available-for-sale securities:
Cost	36	34
Unrealized Gains	1	0
Unrealized Losses	0	0
Fair Value	37	34
Non-U.S. government and agency securities \| Level 2 \| Investments
Available-for-sale securities:
Fair Value	37	34
Non-U.S. government and agency securities \| Level 2 \| Other Assets
Available-for-sale securities:
Fair Value	0	0
Other asset-backed securities \| Level 2
Available-for-sale securities:
Cost	518	499
Unrealized Gains	4	1
Unrealized Losses	(7)	(20)
Fair Value	515	480
Other asset-backed securities \| Level 2 \| Investments
Available-for-sale securities:
Fair Value	515	480
Other asset-backed securities \| Level 2 \| Other Assets
Available-for-sale securities:
Fair Value	0	0
Auction rate securities \| Level 3
Available-for-sale securities:
Cost	36	36
Unrealized Gains	0	0
Unrealized Losses	0	(3)
Fair Value	36	33
Auction rate securities \| Level 3 \| Investments
Available-for-sale securities:
Fair Value	0	0
Auction rate securities \| Level 3 \| Other Assets
Available-for-sale securities:
Fair Value	36	$ 33
Time deposit \| Level 2
Held-to-maturity securities:
Cost	886
Unrealized Gains	0
Unrealized Losses	0
Fair Value	886
Time deposit \| Level 2 \| Investments
Held-to-maturity securities:
Fair Value	886
Time deposit \| Level 2 \| Other Assets
Held-to-maturity securities:
Fair Value	$ 0

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