Fair Value Measurements (Tables)

6 Months Ended

Mar. 30, 2025

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Assets And Liabilities Measured At Fair Value On A Recurring Basis

			Fair Value Measurements at Reporting Date Using
	Balance at March 30, 2025		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant  Other Observable Inputs (Level 2)		Significant Unobservable  Inputs (Level 3)
Assets:
Cash and cash equivalents	$	2,671.4	$	2,671.4	$	—	$	—
Short-term investments:
Available-for-sale debt securities:
Corporate debt securities	82.4		—		71.0		11.4
U.S. government treasury securities	81.3		81.3		—		—
Total available-for-sale debt securities	163.7		81.3		71.0		11.4
Structured deposits	96.8		—		96.8		—
Marketable equity securities	79.7		79.7		—		—
Total short-term investments	340.2		161.0		167.8		11.4
Prepaid expenses and other current assets:
Derivative assets	51.2		—		51.2		—
Long-term investments:
Available-for-sale debt securities:
Corporate debt securities	110.3		—		85.1		25.2
Mortgage and other asset-backed securities	68.0		—		68.0		—
State and local government obligations	3.8		—		3.8		—
U.S. government treasury securities	40.0		40.0		—		—
Total available-for-sale debt securities	222.1		40.0		156.9		25.2
Total long-term investments	222.1		40.0		156.9		25.2
Other long-term assets:
Derivative assets	271.7		—		271.7		—
Total assets	$	3,556.6	$	2,872.4	$	647.6	$	36.6
Liabilities:
Accrued liabilities:
Derivative liabilities	$	0.9	$	—	$	0.9	$	—
Other long-term liabilities:
Derivative liabilities	22.4		—		22.4		—
Total liabilities	$	23.3	$	—	$	23.3	$	—

			Fair Value Measurements at Reporting Date Using
	Balance at September 29, 2024		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable  Inputs (Level 3)
Assets:
Cash and cash equivalents	$	3,286.2	$	3,286.2	$	—	$	—
Short-term investments:
Available-for-sale debt securities:
Corporate debt securities	51.8		—		51.8		—
Foreign corporate bonds	0.2		—		0.2		—
Mortgage and other asset-backed securities	0.4		—		0.4		—
State and local government obligations	1.4		—		1.4		—
U.S. government treasury securities	36.9		36.9		—		—
Total available-for-sale debt securities	90.7		36.9		53.8		—
Structured deposits	84.1		—		84.1		—
Marketable equity securities	82.2		82.2		—		—
Total short-term investments	257.0		119.1		137.9		—
Prepaid expenses and other current assets:
Derivative assets	8.7		—		8.7		—
Long-term investments:
Available-for-sale debt securities:
Corporate debt securities	112.8		—		101.8		11.0
Mortgage and other asset-backed securities	64.4		—		64.4		—
State and local government obligations	3.7		—		3.7		—
U.S. government treasury securities	94.9		94.9		—		—
Total available-for-sale debt securities	275.8		94.9		169.9		11.0
Structured deposits	0.2		—		0.2		—
Total long-term investments	276.0		94.9		170.1		11.0
Other long-term assets:
Derivative assets	179.1		—		179.1		—
Total assets	$	4,007.0	$	3,500.2	$	495.8	$	11.0
Liabilities:
Accrued liabilities:
Derivative liabilities	$	29.2	$	—	$	29.2	$	—
Other long-term liabilities:
Derivative liabilities	56.7		—		56.7		—
Total liabilities	$	85.9	$	—	$	85.9	$	—