Financial Instruments - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions | Mar. 26, 2022 | Sep. 25, 2021 |
Debt Securities, Available-for-sale [Line Items] | | |
Cash, Cash Equivalents and Marketable Securities, Adjusted Cost | $ 201,293 | $ 189,961 |
Cash Equivalents and Marketable Securities, Unrealized Gains | 151 | 1,753 |
Cash Equivalents and Marketable Securities, Unrealized Losses | (8,714) | (1,198) |
Cash, Cash Equivalents and Marketable Securities, Fair Value | 192,730 | 190,516 |
Cash and Cash Equivalents | 28,098 | 34,940 |
Current Marketable Securities | 23,413 | 27,699 |
Non-Current Marketable Securities | 141,219 | 127,877 |
Total marketable securities that were restricted from general use | 15,400 | 17,900 |
Level 1 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Equity, Adjusted Cost | 7,883 | 9,783 |
Marketable Securities, Equity, Unrealized Gains | 7 | 11 |
Marketable Securities, Equity, Unrealized Losses | (9) | (1) |
Marketable Securities, Equity, Fair Value | 7,881 | 9,793 |
Cash and Cash Equivalents | 7,653 | 9,608 |
Current Marketable Securities | 228 | 185 |
Non-Current Marketable Securities | 0 | 0 |
Level 2 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Debt, Adjusted Cost | 179,112 | 162,873 |
Marketable Securities, Debt, Unrealized Gains | 144 | 1,742 |
Marketable Securities, Debt, Unrealized Losses | (8,705) | (1,197) |
Marketable Securities, Debt, Fair Value | 170,551 | 163,418 |
Cash and Cash Equivalents | 6,147 | 8,027 |
Current Marketable Securities | 23,185 | 27,514 |
Non-Current Marketable Securities | 141,219 | 127,877 |
Cash | | |
Debt Securities, Available-for-sale [Line Items] | | |
Cash | 14,298 | 17,305 |
Cash and Cash Equivalents | 14,298 | 17,305 |
Current Marketable Securities | 0 | 0 |
Non-Current Marketable Securities | 0 | 0 |
Money market funds | Level 1 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Equity, Adjusted Cost | 7,653 | 9,608 |
Marketable Securities, Equity, Unrealized Gains | 0 | 0 |
Marketable Securities, Equity, Unrealized Losses | 0 | 0 |
Marketable Securities, Equity, Fair Value | 7,653 | 9,608 |
Cash and Cash Equivalents | 7,653 | 9,608 |
Current Marketable Securities | 0 | 0 |
Non-Current Marketable Securities | 0 | 0 |
Mutual funds | Level 1 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Equity, Adjusted Cost | 230 | 175 |
Marketable Securities, Equity, Unrealized Gains | 7 | 11 |
Marketable Securities, Equity, Unrealized Losses | (9) | (1) |
Marketable Securities, Equity, Fair Value | 228 | 185 |
Cash and Cash Equivalents | 0 | 0 |
Current Marketable Securities | 228 | 185 |
Non-Current Marketable Securities | 0 | 0 |
Equity securities | Level 2 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Equity, Adjusted Cost | 1,527 | 1,527 |
Marketable Securities, Equity, Unrealized Gains | 0 | 0 |
Marketable Securities, Equity, Unrealized Losses | (1,132) | (564) |
Marketable Securities, Equity, Fair Value | 395 | 963 |
Cash and Cash Equivalents | 0 | 0 |
Current Marketable Securities | 395 | 963 |
Non-Current Marketable Securities | 0 | 0 |
U.S. Treasury securities | Level 2 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Debt, Adjusted Cost | 28,711 | 22,878 |
Marketable Securities, Debt, Unrealized Gains | 2 | 102 |
Marketable Securities, Debt, Unrealized Losses | (1,037) | (77) |
Marketable Securities, Debt, Fair Value | 27,676 | 22,903 |
Cash and Cash Equivalents | 2,306 | 3,596 |
Current Marketable Securities | 3,554 | 6,625 |
Non-Current Marketable Securities | 21,816 | 12,682 |
U.S. agency securities | Level 2 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Debt, Adjusted Cost | 6,561 | 8,949 |
Marketable Securities, Debt, Unrealized Gains | 0 | 2 |
Marketable Securities, Debt, Unrealized Losses | (407) | (64) |
Marketable Securities, Debt, Fair Value | 6,154 | 8,887 |
Cash and Cash Equivalents | 251 | 1,775 |
Current Marketable Securities | 683 | 1,930 |
Non-Current Marketable Securities | 5,220 | 5,182 |
Non-U.S. government securities | Level 2 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Debt, Adjusted Cost | 18,868 | 20,201 |
Marketable Securities, Debt, Unrealized Gains | 44 | 211 |
Marketable Securities, Debt, Unrealized Losses | (551) | (101) |
Marketable Securities, Debt, Fair Value | 18,361 | 20,311 |
Cash and Cash Equivalents | 25 | 390 |
Current Marketable Securities | 4,526 | 3,091 |
Non-Current Marketable Securities | 13,810 | 16,830 |
Certificates of deposit and time deposits | Level 2 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Debt, Adjusted Cost | 2,872 | 1,300 |
Marketable Securities, Debt, Unrealized Gains | 0 | 0 |
Marketable Securities, Debt, Unrealized Losses | 0 | 0 |
Marketable Securities, Debt, Fair Value | 2,872 | 1,300 |
Cash and Cash Equivalents | 2,221 | 490 |
Current Marketable Securities | 601 | 810 |
Non-Current Marketable Securities | 50 | 0 |
Commercial paper | Level 2 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Debt, Adjusted Cost | 2,913 | 2,639 |
Marketable Securities, Debt, Unrealized Gains | 0 | 0 |
Marketable Securities, Debt, Unrealized Losses | 0 | 0 |
Marketable Securities, Debt, Fair Value | 2,913 | 2,639 |
Cash and Cash Equivalents | 1,310 | 1,776 |
Current Marketable Securities | 1,603 | 863 |
Non-Current Marketable Securities | 0 | 0 |
Corporate debt securities | Level 2 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Debt, Adjusted Cost | 93,057 | 83,883 |
Marketable Securities, Debt, Unrealized Gains | 94 | 1,242 |
Marketable Securities, Debt, Unrealized Losses | (4,266) | (267) |
Marketable Securities, Debt, Fair Value | 88,885 | 84,858 |
Cash and Cash Equivalents | 34 | 0 |
Current Marketable Securities | 11,309 | 12,327 |
Non-Current Marketable Securities | 77,542 | 72,531 |
Municipal securities | Level 2 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Debt, Adjusted Cost | 990 | 967 |
Marketable Securities, Debt, Unrealized Gains | 1 | 14 |
Marketable Securities, Debt, Unrealized Losses | (22) | 0 |
Marketable Securities, Debt, Fair Value | 969 | 981 |
Cash and Cash Equivalents | 0 | 0 |
Current Marketable Securities | 162 | 130 |
Non-Current Marketable Securities | 807 | 851 |
Mortgage- and asset-backed securities | Level 2 | | |
Debt Securities, Available-for-sale [Line Items] | | |
Marketable Securities, Debt, Adjusted Cost | 23,613 | 20,529 |
Marketable Securities, Debt, Unrealized Gains | 3 | 171 |
Marketable Securities, Debt, Unrealized Losses | (1,290) | (124) |
Marketable Securities, Debt, Fair Value | 22,326 | 20,576 |
Cash and Cash Equivalents | 0 | 0 |
Current Marketable Securities | 352 | 775 |
Non-Current Marketable Securities | $ 21,974 | $ 19,801 |