v3.20.4
Stock-Based Compensation - Summary of Equity Awards (Details) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions
12 Months Ended
Jan. 31, 2021
Jan. 26, 2020
Jan. 27, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Awards granted (in shares) 9    
Weighted average grant date fair value (in dollars per share) $ 307.25    
Shares purchased (in shares) 1 1 1
Summary of unearned SBC expense      
Unearned stock-based compensation expense $ 3,170    
RSUs, PSUs and Market-based PSUs      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Awards granted (in shares) 9 7 4
Estimated total grant-date fair value $ 2,764 $ 1,282 $ 1,109
Weighted average grant date fair value (in dollars per share) $ 307.25 $ 184.47 $ 258.26
Summary of unearned SBC expense      
Estimated weighted average amortization period 2 years 6 months    
Employee Stock Purchase Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted average grant date fair value (in dollars per share) $ 67.65 64.87 38.51
Weighted average price (in dollars per share) $ 139.19 $ 148.76 $ 107.48
Summary of unearned SBC expense      
Estimated weighted average amortization period 10 months 24 days    
Fair Value Assumptions      
Risk free interest rate, minimum 0.10% 1.50% 1.60%
Risk free interest rate, maximum 1.60% 2.60% 2.80%
Volatility rate, minimum 26.00% 30.00% 24.00%
Volatility rate, maximum 89.00% 82.00% 75.00%
Employee Stock Purchase Plan | Minimum      
Fair Value Assumptions      
Weighted average expected life (in years) 1 month 6 days 1 month 6 days 1 month 6 days
Dividend yield 0.10% 0.30% 0.30%
Employee Stock Purchase Plan | Maximum      
Fair Value Assumptions      
Weighted average expected life (in years) 2 years 2 years 2 years
Dividend yield 0.30% 0.40% 0.40%