Available-for-Sale Debt Investments and Equity Investments (Summary of Available-for-sale Debt Investments and Equity Investments) (Details) - USD ($) $ in Millions	Oct. 27, 2018	Jul. 28, 2018
Investments, Debt and Equity Securities [Abstract]
Available-for-sale debt investments	$ 34,183	$ 37,009
Marketable equity securities	0	605
Total investments	34,183	37,614
Non-marketable equity securities included in other assets	1,125	978
Equity method investments included in other assets	115	118
Total	$ 35,423	$ 38,710

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of investment in equity security without readily determinable fair value.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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