v3.26.1
Equity and Other Equity Items - Narrative (Details) - JPY (¥)
shares in Thousands, ¥ in Millions
12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Equity [Line Items]      
Number of shares outstanding (in shares) 1,591,229 1,590,950 1,582,419
Disposal of treasury shares   ¥ 0 ¥ 1
Issue of equity ¥ 1,186 36,178 502
Acquisition of treasury shares 51,638 51,925 ¥ 2,367
Equity-Settled LTIP      
Equity [Line Items]      
Disposal of treasury shares ¥ 73,760 ¥ 24,999  
Board of Directors resolution      
Equity [Line Items]      
Treasury shares acquired (in shares) 11,824 11,544  
Treasury shares | Equity-Settled LTIP      
Equity [Line Items]      
Increase (decrease) in number of shares outstanding (in shares) (17,271) (7,327)  
Ordinary shares | Equity-Settled LTIP      
Equity [Line Items]      
Increase (decrease) in number of shares outstanding (in shares)   8,519  
ESOP and BIP Trust      
Equity [Line Items]      
Treasury shares acquired (in shares) 401 460  
Number of treasury shares sold (in shares) 865 783  
Treasury shares      
Equity [Line Items]      
Number of shares outstanding (in shares) 11,392 17,300 13,405
Disposal of treasury shares   ¥ 0 ¥ 0
Acquisition of treasury shares ¥ 51,618 51,905 ¥ 2,367
Treasury shares | Board of Directors resolution      
Equity [Line Items]      
Acquisition of treasury shares ¥ 49,978 ¥ 49,978  
Treasury shares | ESOP and BIP Trust      
Equity [Line Items]      
Number of shares outstanding (in shares) 5,102 5,565 5,888
Share capital      
Equity [Line Items]      
Issue of equity ¥ 593 ¥ 18,089 ¥ 251
Share capital | Equity-Settled LTIP      
Equity [Line Items]      
Issue of equity   18,064  
Share premium      
Equity [Line Items]      
Disposal of treasury shares   0 0
Issue of equity 593 18,089 ¥ 251
Acquisition of treasury shares ¥ 20 20  
Share premium | Equity-Settled LTIP      
Equity [Line Items]      
Issue of equity   ¥ 18,064