v3.26.3
Note 5 - Financial Instruments Measured at Fair Value - Assets Measured at Fair Value on Recurring Basis (Details) - USD ($)
$ in Thousands
Sep. 26, 2026
Dec. 27, 2025
Short-term investments $ 235,645 $ 256,928
Corporate Debt Securities [Member]    
Short-term investments [1] 117,778 150,361
Certificates of Deposit [Member]    
Short-term investments 70,007 58,156
US Treasury Securities [Member]    
Short-term investments 31,393 37,652
Asset-Backed Securities [Member]    
Short-term investments 15,759 10,056
Debt Security, Government, Non-US [Member]    
Short-term investments 708 703
Fair Value, Recurring [Member]    
Assets, Fair Value Disclosure 507,948 483,981
Fair Value, Recurring [Member] | Corporate Debt Securities [Member]    
Short-term investments 138,091 183,611
Fair Value, Recurring [Member] | Certificates of Deposit [Member]    
Short-term investments 70,007 58,156
Fair Value, Recurring [Member] | US Treasury Securities [Member]    
Short-term investments 31,393 37,652
Fair Value, Recurring [Member] | Asset-Backed Securities [Member]    
Short-term investments 15,759 10,056
Fair Value, Recurring [Member] | Debt Security, Government, Non-US [Member]    
Short-term investments 708 703
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]    
Assets, Fair Value Disclosure 136,566 142,091
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Corporate Debt Securities [Member]    
Short-term investments 0 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Certificates of Deposit [Member]    
Short-term investments 0 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | US Treasury Securities [Member]    
Short-term investments 0 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Asset-Backed Securities [Member]    
Short-term investments 0 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Debt Security, Government, Non-US [Member]    
Short-term investments 0 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]    
Assets, Fair Value Disclosure 371,382 341,890
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member]    
Short-term investments 138,091 183,611
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Certificates of Deposit [Member]    
Short-term investments 70,007 58,156
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US Treasury Securities [Member]    
Short-term investments 31,393 37,652
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Asset-Backed Securities [Member]    
Short-term investments 15,759 10,056
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Debt Security, Government, Non-US [Member]    
Short-term investments 708 703
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]    
Assets, Fair Value Disclosure 0 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities [Member]    
Short-term investments 0 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Certificates of Deposit [Member]    
Short-term investments 0 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | US Treasury Securities [Member]    
Short-term investments 0 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Asset-Backed Securities [Member]    
Short-term investments 0 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Debt Security, Government, Non-US [Member]    
Short-term investments 0 0
Fair Value, Recurring [Member] | Cash [Member]    
Cash and cash equivalents 136,566 142,091
Fair Value, Recurring [Member] | Cash [Member] | Fair Value, Inputs, Level 1 [Member]    
Cash and cash equivalents 136,566 142,091
Fair Value, Recurring [Member] | Cash [Member] | Fair Value, Inputs, Level 2 [Member]    
Cash and cash equivalents 0 0
Fair Value, Recurring [Member] | Cash [Member] | Fair Value, Inputs, Level 3 [Member]    
Cash and cash equivalents 0 0
Fair Value, Recurring [Member] | Money Market Funds [Member]    
Cash and cash equivalents 115,424 51,712
Fair Value, Recurring [Member] | Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]    
Cash and cash equivalents 0 0
Fair Value, Recurring [Member] | Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member]    
Cash and cash equivalents 115,424 51,712
Fair Value, Recurring [Member] | Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member]    
Cash and cash equivalents $ 0 $ 0
[1] Corporate debt securities include investments in financial and other corporate institutions. No single issuer represents a significant portion of the total corporate debt securities portfolio.