Investments and Fair Value Measurements (Schedule Of Financial Assets Carried At Fair Value) (Details) - USD ($) $ in Thousands | 12 Months Ended |
Sep. 30, 2022 | Sep. 24, 2021 |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Cash Equivalents, at Carrying Value | | $ 620,128 | | | |
Cash | | | | $ 1,225,380 | |
Short-term investments, cost | | 432,134 | | 330,129 | |
Short-term investments, unrealized gains | | 0 | | | |
Short-term investments, unrealized losses | | (1) | | 0 | |
Short-term investments, total | | 426,149 | | 330,401 | |
Long-term investments, Total | | | | 62,819 | |
Total cash, cash equivalents, and investments, cost | | 917,841 | | 1,326,765 | |
Total cash, cash equivalents, and investments, unrealized gains | | 13 | | 325 | |
Total cash, cash equivalents, and investments, unrealized losses | | (6,000) | | (52) | |
Total cash, cash equivalents, and investments, total | | 911,854 | | 1,327,038 | |
Assets | | $ 620,127 | | $ 1,225,380 | |
Derivative Liability, Current, Statement of Financial Position [Extensible Enumeration] | | Accrued liabilities | | Accrued liabilities | |
Derivative Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] | | Other non-current liabilities | | | |
Derivative Asset, Current, Statement of Financial Position [Extensible Enumeration] | | | | Prepaid expenses and other current assets | |
Equity Method Investments | | $ 5,900 | | | |
Government bonds | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments, Cost | | 57,417 | | $ 100 | |
Short-term investments, Unrealized Gains | | 0 | | 2 | |
Short-term investments, Unrealized Losses | | (705) | | 0 | |
Short-term investments, Total | | 56,712 | | 102 | |
Long-term investments, Cost | | 43,816 | | 11,784 | |
Long-term investments, Unrealized Gains | | 0 | | 38 | |
Long-term investments, Unrealized Losses | | (2,222) | | 16 | |
Long-term investments, Total | | 41,594 | | 11,806 | |
U.S. agency securities | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments, Cost | | | | 1,096 | |
Long-term investments, Cost | | 861 | | 2,264 | |
Long-term investments, Unrealized Gains | | 0 | | 13 | |
Long-term investments, Unrealized Losses | | (39) | | 2 | |
Long-term investments, Total | | 822 | | 2,275 | |
Commercial paper | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments, Cost | | 8,786 | | 5,184 | |
Short-term investments, Unrealized Gains | | 1 | | 2 | |
Short-term investments, Unrealized Losses | | (15) | | 0 | |
Short-term investments, Total | | 8,772 | | 5,186 | |
Total cash, cash equivalents, and investments, cost | | 5,770 | | 0 | |
Total cash, cash equivalents, and investments, unrealized gains | | 15 | | 0 | |
Corporate bonds | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments, Cost | | 72,730 | | 18,850 | |
Short-term investments, Unrealized Gains | | 0 | | 116 | |
Short-term investments, Unrealized Losses | | (734) | | 0 | |
Short-term investments, Total | | 71,996 | | 18,966 | |
Long-term investments, Cost | | 29,684 | | 32,116 | |
Long-term investments, Unrealized Gains | | 4 | | 61 | |
Long-term investments, Unrealized Losses | | (1,349) | | 25 | |
Long-term investments, Total | | 28,339 | | 32,152 | |
Municipal debt securities | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments, Cost | | 25,589 | | 11,660 | |
Short-term investments, Unrealized Gains | | 0 | | 29 | |
Short-term investments, Unrealized Losses | | (241) | | 1 | |
Short-term investments, Total | | 25,348 | | 11,688 | |
Long-term investments, Cost | | 21,483 | | 10,080 | |
Long-term investments, Unrealized Gains | | 0 | | 58 | |
Long-term investments, Unrealized Losses | | (626) | | 8 | |
Long-term investments, Total | | 20,857 | | 10,130 | |
Total cash, cash equivalents, and investments, cost | | 40,119 | | 7,031 | |
Other long-term investments | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Long-term investments, Cost | | 10,902 | [1] | 6,456 | [2] |
Long-term investments, Unrealized Gains | | 0 | [1] | 0 | [2] |
Long-term investments, Unrealized Losses | | 0 | [1] | 0 | [2] |
Long-term investments, Total | | 10,902 | [1] | 6,456 | [2] |
Long-term investments | | 5,000 | | | |
Short-term investments | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments, Cost | | 190,967 | | 38,685 | |
Short-term investments, Unrealized Gains | | 9 | | 155 | |
Short-term investments, Unrealized Losses | | (1,763) | | 1 | |
Short-term investments, Total | | 189,213 | | 38,839 | |
Long-term investments | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Long-term investments, Cost | | 106,746 | | 62,700 | |
Long-term investments, Unrealized Gains | | 4 | | 170 | |
Long-term investments, Unrealized Losses | | (4,236) | | 51 | |
Long-term investments, Total | | 102,514 | | | |
Certificates of Deposit | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments, Cost | | 23,033 | | 1,795 | |
Short-term investments, Unrealized Gains | | 8 | | 0 | |
Short-term investments, Unrealized Losses | | (47) | | 0 | |
Short-term investments, Total | | 22,994 | | 1,795 | |
U.S. agency securities | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments, Cost | | 3,412 | | | |
Short-term investments, Unrealized Gains | | 0 | | 6 | |
Short-term investments, Unrealized Losses | | (21) | | 0 | |
Short-term investments, Total | | 3,391 | | 1,102 | |
Cash | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Cash Equivalents, at Carrying Value | | 474,813 | | | |
Cash | | 474,813 | | 990,182 | |
Money market funds | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Cash Equivalents, at Carrying Value | | 134,987 | | | |
Cash | | 134,987 | | 235,198 | |
Level 1 | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Cash | | 609,800 | | 1,225,380 | |
Short-term investments | | 52,833 | | 102 | |
Long-term investments | | 38,055 | | 4,966 | |
Assets | | 700,688 | | 1,230,448 | |
Derivative Liability, Current | | 0 | | 0 | |
Derivative Liability, Noncurrent | | 0 | | | |
Derivative Asset, Current | | | | 0 | |
Level 1 | Government bonds | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments | | 52,833 | | 102 | |
Long-term investments | | 38,055 | | 4,966 | |
Level 1 | Other long-term investments | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Long-term investments | [2] | | | 0 | |
Level 1 | Investments held in supplemental retirement plan: | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Assets | | 4,225 | | 4,975 | |
Liabilities | | 4,225 | | 4,975 | |
Level 1 | Cash | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Cash | | 474,813 | | 990,182 | |
Level 1 | Money market funds | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Cash | | 134,987 | | 235,198 | |
Level 2 | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Cash | | 10,327 | | 0 | |
Short-term investments | | 136,380 | | 38,737 | |
Long-term investments | | 53,557 | | 51,397 | |
Assets | | 200,264 | | 90,134 | |
Derivative Liability, Current | | (4,882) | | (197) | |
Derivative Liability, Noncurrent | | (420) | | | |
Derivative Asset, Current | | | | 689 | |
Level 2 | Government bonds | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments | | 3,879 | | 0 | |
Long-term investments | | 3,539 | | 6,840 | |
Level 2 | U.S. agency securities | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Long-term investments | | 822 | | 2,275 | |
Level 2 | Commercial paper | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments | | 8,772 | | 5,186 | |
Level 2 | Corporate bonds | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments | | 71,996 | | 18,966 | |
Long-term investments | | 28,339 | | 32,152 | |
Level 2 | Municipal debt securities | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments | | 25,348 | | 11,688 | |
Long-term investments | | 20,857 | | 10,130 | |
Level 2 | Certificates of Deposit | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments | | 22,994 | | 1,795 | |
Level 2 | U.S. agency securities | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Short-term investments | | 3,391 | | 1,102 | |
Level 3 | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Assets | | 0 | | 0 | |
Derivative Liability, Current | | 0 | | 0 | |
Derivative Liability, Noncurrent | | 0 | | | |
Derivative Asset, Current | | | | 0 | |
Derivative Financial Instruments, Liabilities, Current | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Currency derivatives as hedge instruments, liabilities, cost | | | | 0 | |
Currency derivatives as hedge instruments, unrealized gains | | 0 | | 0 | |
Currency derivatives as hedge instruments, unrealized loss | | (4,882) | | (197) | |
Derivative Financial Instruments, Liabilities, Current, Amortized Cost Basis | | 0 | | | |
Derivative Liability, Current | | (4,882) | | (197) | |
us-Derivative Financial Instruments, Liabilities, Noncurrent | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Currency derivatives as hedge instruments, unrealized gains | | 0 | | | |
Currency derivatives as hedge instruments, unrealized loss | | (420) | | | |
Derivative Liability, Noncurrent | | (420) | | | |
Derivative Financial Instruments, Liabilities, Noncurrent, Amortized Cost Basis | | $ 0 | | | |
Derivative Financial Instruments, Assets, Current | | | | | |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | | | | | |
Currency derivatives as hedge instruments, assets, cost | | | | 0 | |
Currency derivatives as hedge instruments, unrealized gains | | | | 689 | |
Currency derivatives as hedge instruments, unrealized loss | | | | 0 | |
Derivative Asset, Current | | | | $ 689 | |
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[1]Other investments as of September 30, 2022 is comprised of an equity method investment of $5.9 million and an equity security without a readily determinable fair value of $5.0 million.[2]Other investments as of September 24, 2021 is comprised of one equity method investment. | |