v3.25.4
Long-term Debt - Schedule of Long-term Debt (Details) - USD ($)
$ / shares in Units, $ in Millions
3 Months Ended 6 Months Ended 12 Months Ended
Dec. 28, 2025
Dec. 22, 2025
Sep. 29, 2025
Dec. 28, 2025
Sep. 29, 2025
Dec. 28, 2025
Dec. 29, 2024
Jun. 29, 2025
Debt Instrument [Line Items]                
Initial Principal $ 2,090.6     $ 2,090.6   $ 2,090.6   $ 6,325.0
Repayment of principal           (164.8)   0.0
Conversion to common stock           (18.5)   0.0
Outstanding principal 1,907.3     1,907.3   1,907.3   6,658.2
Embedded derivative on New 2L Renesas Convertible Notes 103.5     103.5   103.5    
Unamortized premium/discount (47.1)     (47.1)   (47.1)   (120.2)
Ending Balance 1,963.7     1,963.7   1,963.7   6,538.0
Equity component 159.3     159.3   159.3   0.0
Fair Value $ 1,984.1     1,984.1   $ 1,984.1   $ 2,647.3
Repayments of senior debt       0.0 $ 308.5   $ 0.0  
Paid-in-kind interest on long-term debt       $ 10.8 $ 0.0   $ 5.9  
Substantial premium on 2L Convertible Notes     $ 168.8          
Additional Paid-in Capital                
Debt Instrument [Line Items]                
Substantial premium on 2L Convertible Notes     $ 168.8          
Convertible Notes | 1.75% Convertible Notes                
Debt Instrument [Line Items]                
Stated interest rate (as a percent) 1.75%     1.75%   1.75%   1.75%
Effective interest rate (as a percent)               2.20%
Initial Principal               $ 575.0
Repayment of principal               0.0
Conversion to common stock               0.0
Outstanding principal               575.0
Unamortized premium/discount               (2.0)
Ending Balance               573.0
Equity component               0.0
Fair Value               $ 145.2
Convertible Notes | 0.25% Convertible Notes                
Debt Instrument [Line Items]                
Stated interest rate (as a percent) 0.25%     0.25%   0.25%   0.25%
Effective interest rate (as a percent)               0.60%
Initial Principal               $ 750.0
Repayment of principal               0.0
Conversion to common stock               0.0
Outstanding principal               750.0
Unamortized premium/discount               (7.9)
Ending Balance               742.1
Equity component               0.0
Fair Value               $ 186.6
Convertible Notes | 1.875% Convertible Notes                
Debt Instrument [Line Items]                
Stated interest rate (as a percent) 1.875%     1.875%   1.875%   1.875%
Effective interest rate (as a percent)               2.10%
Initial Principal               $ 1,750.0
Repayment of principal               0.0
Conversion to common stock               0.0
Outstanding principal               1,750.0
Unamortized premium/discount               (20.7)
Ending Balance               1,729.3
Equity component               0.0
Fair Value               $ 450.6
Convertible Notes | New 2L Non-Renesas Convertible Notes                
Debt Instrument [Line Items]                
Stated interest rate (as a percent)     2.50%   2.50%      
Effective interest rate (as a percent) 3.00%     3.00%   3.00%    
Initial Principal $ 331.4     $ 331.4   $ 331.4    
Repayment of principal           0.0    
Conversion to common stock (18.5)         (18.5)    
Outstanding principal 312.9     312.9   312.9    
Embedded derivative on New 2L Renesas Convertible Notes 0.0     0.0   0.0    
Unamortized premium/discount (7.2)     (7.2)   (7.2)    
Ending Balance 305.7     305.7   305.7    
Equity component 159.3     159.3   159.3    
Fair Value $ 493.6     $ 493.6   $ 493.6    
Debt instrument, convertible, conversion price (in USD per share)     $ 12.23   $ 12.23      
Debt conversion, converted instrument, shares issued (in shares) 1,500,000              
Convertible Notes | New 2L Renesas Convertible Notes(5)                
Debt Instrument [Line Items]                
Stated interest rate (as a percent)     2.50%   2.50%      
Effective interest rate (as a percent) 12.30%     12.30%   12.30%    
Initial Principal $ 203.6     $ 203.6   $ 203.6    
Repayment of principal           0.0    
Conversion to common stock           0.0    
Outstanding principal 203.6     203.6   203.6    
Embedded derivative on New 2L Renesas Convertible Notes 103.5     103.5   103.5    
Unamortized premium/discount (79.3)     (79.3)   (79.3)    
Ending Balance 227.8     227.8   227.8    
Equity component 0.0     0.0   0.0    
Fair Value $ 215.8     $ 215.8   $ 215.8    
Debt instrument, convertible, conversion price (in USD per share)     $ 18.35   $ 18.35      
Convertible Notes | 2L Convertible Notes                
Debt Instrument [Line Items]                
Percentage of equity component not related to outstanding debt due to conversions 5.60%     5.60%   5.60%    
Senior Notes | 2030 Senior Notes                
Debt Instrument [Line Items]                
Effective interest rate (as a percent)               16.30%
Initial Principal               $ 1,250.0
Repayment of principal               0.0
Conversion to common stock               0.0
Outstanding principal               1,521.2
Unamortized premium/discount               (52.3)
Ending Balance               1,468.9
Equity component               0.0
Fair Value               $ 1,308.2
Senior Notes | New Senior Secured Notes                
Debt Instrument [Line Items]                
Effective interest rate (as a percent) 12.90%     12.90%   12.90%    
Initial Principal $ 1,259.2     $ 1,259.2   $ 1,259.2    
Repayment of principal           (164.8)    
Conversion to common stock           0.0    
Outstanding principal 1,094.4     1,094.4   1,094.4    
Embedded derivative on New 2L Renesas Convertible Notes 0.0     0.0   0.0    
Unamortized premium/discount 104.2     104.2   104.2    
Ending Balance 1,198.6     1,198.6   1,198.6    
Equity component 0.0     0.0   0.0    
Fair Value $ 1,034.2     $ 1,034.2   $ 1,034.2    
Debt instrument, repurchased face amount   $ 175.0            
Repayments of senior debt   197.9            
Paid-in-kind interest on long-term debt   $ 10.2            
Senior Notes | New 2L Non-Convertible Notes                
Debt Instrument [Line Items]                
Effective interest rate (as a percent) 12.50%   7.00% 12.50% 7.00% 12.50%    
Initial Principal $ 296.4     $ 296.4   $ 296.4    
Repayment of principal           0.0    
Conversion to common stock           0.0    
Outstanding principal 296.4     296.4   296.4    
Embedded derivative on New 2L Renesas Convertible Notes 0.0     0.0   0.0    
Unamortized premium/discount (64.8)     (64.8)   (64.8)    
Ending Balance 231.6     231.6   231.6    
Equity component 0.0     0.0   0.0    
Fair Value $ 240.5     $ 240.5   $ 240.5    
Unsecured Debt | CRD Agreement Deposits                
Debt Instrument [Line Items]                
Effective interest rate (as a percent)               6.80%
Initial Principal               $ 2,000.0
Repayment of principal               0.0
Conversion to common stock               0.0
Outstanding principal               2,062.0
Unamortized premium/discount               (37.3)
Ending Balance               2,024.7
Equity component               0.0
Fair Value               $ 556.7