Fair Value Measures - Narrative (Details) - USD ($)	Mar. 30, 2024	Sep. 30, 2023	Mar. 25, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash and cash equivalents	$ 901,382,000	$ 258,770,000	$ 256,954,000
Fair Value, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total liabilities	0	$ 0
U.S. Treasury securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Amortized cost	48,700,000
Gross unrealized gain	1,300,000
Gross unrealized loss	0
Fair value	50,000,000
Cash and cash equivalents	$ 0