v3.26.1
Sales Revenue - Summary of Revenue Expected to be Recognized in the Future Related to Performance Obligations that are Unsatisfied (or Partially Unsatisfied) (Detail) - JPY (¥)
¥ in Millions
Mar. 31, 2026
Mar. 31, 2025
Disclosure of disaggregation of revenue from contracts with customers [line items]    
Total ¥ 689,787 ¥ 635,932
Within 1 year [member]    
Disclosure of disaggregation of revenue from contracts with customers [line items]    
Total 255,808 245,826
Between 1 and 5 years [member]    
Disclosure of disaggregation of revenue from contracts with customers [line items]    
Total 402,934 363,831
Later than 5 years [member]    
Disclosure of disaggregation of revenue from contracts with customers [line items]    
Total ¥ 31,045 ¥ 26,275