Investments, Marketable Securities, Credit Losses on and Maturities of Debt Securities (Details) (USD $) In Millions, unless otherwise specified	Jul. 25, 2014	Apr. 25, 2014
Long-term
Investments	$ 12,626	$ 12,838
Long-term investments	813	821
Credit Loss Portion of Other-than-temporary Impairments on Debt Securities
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held	4	4
AFS Debt Maturities
Due in one year or less	1,426
Due after one year through five years	5,961
Due after five years through ten years	2,689
Due after ten years	141
Total debt securities	10,217
Investments [Member]
Long-term
Available-for-sale securities, fair value	12,557	12,771
Trading securities, fair value	69	67
Investments Other than Available-for-sale and Trading Securities	0	0
Other Assets
Long-term
Available-for-sale securities, fair value	195	155
Trading securities, fair value	0	0
Investments Other than Available-for-sale and Trading Securities	$ 618	$ 666